ipcs: code shrink

ipcs: code shrink

function                                             old     new   delta
packed_usage                                       32539   32543      +4
format                                                 1       -      -1
do_shm                                               883     880      -3
do_sem                                               636     633      -3
do_msg                                               782     779      -3
ipcs_main                                           1049    1014     -35
------------------------------------------------------------------------------
(add/remove: 0/1 grow/shrink: 1/4 up/down: 4/-45)             Total: -41 bytes

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