[PATCH] fix NULL dereference in inotify_ignore

Don't reassign to watch.  If idr_find() returns NULL, then
put_inotify_watch() will choke.

Signed-off-by: Amy Griffis <amy.griffis@hp.com>
Cc: John McCutchan <john@johnmccutchan.com>
Cc: Robert Love <rlove@rlove.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>