getopt32: remove applet_long_options

FEATURE_GETOPT_LONG made dependent on LONG_OPTS.

The folloving options are removed, now LONG_OPTS enables long options
for affected applets:
FEATURE_ENV_LONG_OPTIONS	FEATURE_EXPAND_LONG_OPTIONS
FEATURE_UNEXPAND_LONG_OPTIONS	FEATURE_MKDIR_LONG_OPTIONS
FEATURE_MV_LONG_OPTIONS		FEATURE_RMDIR_LONG_OPTIONS
FEATURE_ADDGROUP_LONG_OPTIONS	FEATURE_ADDUSER_LONG_OPTIONS
FEATURE_HWCLOCK_LONG_OPTIONS	FEATURE_NSENTER_LONG_OPTS
FEATURE_CHCON_LONG_OPTIONS	FEATURE_RUNCON_LONG_OPTIONS

They either had a small number of long options, or their long options are
essential.

Example: upstream addgroup and adduser have ONLY longopts,
we should probably go further and get rid
of non-standard short options.

To this end, make addgroup and adduser "select LONG_OPTS".
We had this breakage caused by us even in our own package!
	#if ENABLE_LONG_OPTS || !ENABLE_ADDGROUP
                /* We try to use --gid, not -g, because "standard" addgroup
                 * has no short option -g, it has only long --gid.
                 */
                argv[1] = (char*)"--gid";
	#else
                /* Breaks if system in fact does NOT use busybox addgroup */
                argv[1] = (char*)"-g";
	#endif

xargs: its lone longopt no longer depends on DESKTOP, only on LONG_OPTS.

hwclock TODO: get rid of incompatible -t, -l aliases to --systz, --localtime

Shorten help texts by omitting long option when short opt alternative exists.

Reduction of size comes from the fact that store of an immediate
(an address of longopts) to a fixed address (global variable)
is a longer insn than pushing that immediate or passing it in a register.
This effect is CPU-agnostic.

function                                             old     new   delta
getopt32                                            1350      22   -1328
vgetopt32                                              -    1318   +1318
getopt32long                                           -      24     +24
tftpd_main                                           562     567      +5
scan_recursive                                       376     380      +4
collect_cpu                                          545     546      +1
date_main                                           1096    1095      -1
hostname_main                                        262     259      -3
uname_main                                           259     255      -4
setpriv_main                                         362     358      -4
rmdir_main                                           191     187      -4
mv_main                                              562     558      -4
ipcalc_main                                          548     544      -4
ifenslave_main                                       641     637      -4
gzip_main                                            192     188      -4
gunzip_main                                           77      73      -4
fsfreeze_main                                         81      77      -4
flock_main                                           318     314      -4
deluser_main                                         337     333      -4
cp_main                                              374     370      -4
chown_main                                           175     171      -4
applet_long_options                                    4       -      -4
xargs_main                                           894     889      -5
wget_main                                           2540    2535      -5
udhcpc_main                                         2767    2762      -5
touch_main                                           436     431      -5
tar_main                                            1014    1009      -5
start_stop_daemon_main                              1033    1028      -5
sed_main                                             682     677      -5
script_main                                         1082    1077      -5
run_parts_main                                       330     325      -5
rtcwake_main                                         459     454      -5
od_main                                             2169    2164      -5
nl_main                                              201     196      -5
modprobe_main                                        773     768      -5
mkdir_main                                           160     155      -5
ls_main                                              568     563      -5
install_main                                         773     768      -5
hwclock_main                                         411     406      -5
getopt_main                                          622     617      -5
fstrim_main                                          256     251      -5
env_main                                             198     193      -5
dumpleases_main                                      635     630      -5
dpkg_main                                           3991    3986      -5
diff_main                                           1355    1350      -5
cryptpw_main                                         233     228      -5
cpio_main                                            593     588      -5
conspy_main                                         1135    1130      -5
chpasswd_main                                        313     308      -5
adduser_main                                         887     882      -5
addgroup_main                                        416     411      -5
ftpgetput_main                                       351     345      -6
get_terminal_width_height                            242     234      -8
expand_main                                          690     680     -10
static.expand_longopts                                18       -     -18
static.unexpand_longopts                              27       -     -27
mkdir_longopts                                        28       -     -28
env_longopts                                          30       -     -30
static.ifenslave_longopts                             34       -     -34
mv_longopts                                           46       -     -46
static.rmdir_longopts                                 48       -     -48
packed_usage                                       31739   31687     -52
------------------------------------------------------------------------------
(add/remove: 2/8 grow/shrink: 3/49 up/down: 1352/-1840)      Total: -488 bytes
   text	   data	    bss	    dec	    hex	filename
 915681	    485	   6880	 923046	  e15a6	busybox_old
 915428	    485	   6876	 922789	  e14a5	busybox_unstripped

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/coreutils/mkdir.c b/coreutils/mkdir.c
index 2285118..986353d 100644
--- a/coreutils/mkdir.c
+++ b/coreutils/mkdir.c
@@ -18,11 +18,6 @@
 //config:	default y
 //config:	help
 //config:	mkdir is used to create directories with the specified names.
-//config:
-//config:config FEATURE_MKDIR_LONG_OPTIONS
-//config:	bool "Enable long options"
-//config:	default y
-//config:	depends on MKDIR && LONG_OPTS
 
 //applet:IF_MKDIR(APPLET_NOFORK(mkdir, mkdir, BB_DIR_BIN, BB_SUID_DROP, mkdir))
 
@@ -53,19 +48,6 @@
 
 /* This is a NOFORK applet. Be very careful! */
 
-#if ENABLE_FEATURE_MKDIR_LONG_OPTIONS
-static const char mkdir_longopts[] ALIGN1 =
-	"mode\0"    Required_argument "m"
-	"parents\0" No_argument       "p"
-#if ENABLE_SELINUX
-	"context\0" Required_argument "Z"
-#endif
-#if ENABLE_FEATURE_VERBOSE
-	"verbose\0" No_argument       "v"
-#endif
-	;
-#endif
-
 int mkdir_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int mkdir_main(int argc UNUSED_PARAM, char **argv)
 {
@@ -78,10 +60,17 @@
 	security_context_t scontext;
 #endif
 
-#if ENABLE_FEATURE_MKDIR_LONG_OPTIONS
-	applet_long_options = mkdir_longopts;
-#endif
-	opt = getopt32(argv, "m:pv" IF_SELINUX("Z:"), &smode IF_SELINUX(,&scontext));
+	opt = getopt32long(argv, "m:pv" IF_SELINUX("Z:"),
+			"mode\0"    Required_argument "m"
+			"parents\0" No_argument       "p"
+# if ENABLE_SELINUX
+			"context\0" Required_argument "Z"
+# endif
+# if ENABLE_FEATURE_VERBOSE
+			"verbose\0" No_argument       "v"
+# endif
+			, &smode IF_SELINUX(,&scontext)
+	);
 	if (opt & 1) {
 		mode_t mmode = bb_parse_mode(smode, 0777);
 		if (mmode == (mode_t)-1) {