[PATCH] Make XFS use BH_Unwritten and BH_Delay correctly

Don't hide buffer_unwritten behind buffer_delay() and remove the hack that
clears unexpected buffer_unwritten() states now that it can't happen.

Signed-off-by: Dave Chinner <dgc@sgi.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Timothy Shimmin <tes@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>