dhcp: get rid of static data signal_pipe

function                                             old     new   delta
udhcp_sp_setup                                        65     110     +45
udhcp_sp_fd_set                                       60      59      -1
udhcpd_main                                         1442    1437      -5
udhcpc_main                                         2684    2679      -5
signal_pipe                                            8       -      -8
packed_usage                                       33292   33284      -8
------------------------------------------------------------------------------
(add/remove: 0/1 grow/shrink: 1/4 up/down: 45/-27)             Total: 18 bytes
   text	   data	    bss	    dec	    hex	filename
 952746	    481	   7296	 960523	  ea80b	busybox_old
 952768	    481	   7288	 960537	  ea819	busybox_unstripped

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/networking/udhcp/dhcpc.c b/networking/udhcp/dhcpc.c
index cb85fa9..f040e93 100644
--- a/networking/udhcp/dhcpc.c
+++ b/networking/udhcp/dhcpc.c
@@ -1271,6 +1271,10 @@
 	client_data.sockfd = -1;
 	str_V = "udhcp "BB_VER;
 
+	/* Make sure fd 0,1,2 are open */
+	/* Set up the signal pipe on fds 3,4 - must be before openlog() */
+	udhcp_sp_setup();
+
 	/* Parse command line */
 	opt = getopt32long(argv, "^"
 		/* O,x: list; -T,-t,-A take numeric param */
@@ -1385,14 +1389,10 @@
 		logmode |= LOGMODE_SYSLOG;
 	}
 
-	/* Make sure fd 0,1,2 are open */
-	bb_sanitize_stdio();
 	/* Create pidfile */
 	write_pidfile(client_data.pidfile);
 	/* Goes to stdout (unless NOMMU) and possibly syslog */
 	bb_info_msg("started, v"BB_VER);
-	/* Set up the signal pipe */
-	udhcp_sp_setup();
 	/* We want random_xid to be random... */
 	srand(monotonic_us());