Fixup another round of sparse warnings of the type:
	warning: Using plain integer as NULL pointer
Acked by Stephen.

From: Mika Kukkonen <mika@osdl.org>
Signed-off-by: Chris Wright <chrisw@osdl.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>