autofs: fix doubled word

Change doubled word "is" to "it is".

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Ian Kent <raven@themaw.net>
Link: http://lkml.kernel.org/r/5a82befd-40f8-8dc0-3498-cbc0436cad9b@infradead.org


Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>