[PATCH] ipc: headers_check fix

Fix headers_check #ifdef __KERNEL__ stuff.

Signed-off-by: Cedric Le Goater <clg@fr.ibm.com>
All-the-fault-of: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>