lockdep needs to have the waitqueue lock initialized for on-stack
waitqueues implicitly initialized by DECLARE_COMPLETION().

Annotate mmc_wait_for_req()'s on-stack completion accordingly.

Has no effect on non-lockdep kernels.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>