During testing I've found that the mount pending flag can be left set at
exit from autofs4_lookup after a failed mount request.  This shouldn't be
allowed to happen and causes incorrect error returns.

Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>