run-init: implement -n "dry run"

function                                             old     new   delta
switch_root_main                                     637     706     +69
packed_usage                                       31743   31757     +14
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/0 up/down: 83/0)               Total: 83 bytes
   text	   data	    bss	    dec	    hex	filename
 915247	    563	   5844	 921654	  e1036	busybox_old
 915303	    563	   5844	 921710	  e106e	busybox_unstripped

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2 files changed