register_sysctl_table() fails if sysctl support is not compiled into the
kernel.  The POSIX message queue subsystem aborted it's initialization if
register_sysctl_table() fails, and that causes an oops in sys_mq_open().
The patch fixes that by ignoring failures from register_sysctl_table().

Signed-off-by; Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>