[PATCH] proc: fix linkage with CONFIG_SYSCTL=y, CONFIG_PROC_SYSCTL=n

We're using #ifdef CONFIG_SYSCTL, but we should be using CONFIG_PROC_SYSCTL,
so we get

 fs/built-in.o: In function `proc_root_init':
 /usr/src/linux/fs/proc/root.c:83: undefined reference to `proc_sys_init'

Fix that up and remove an ifdef-in-C.

Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Helge Hafting <helgehaf@aitel.hist.no>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>