xfs: small cleanups for xfs_iomap / __xfs_get_blocks

Remove the flags argument to  __xfs_get_blocks as we can easily derive
it from the direct argument, and remove the unused BMAPI_MMAP flag.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>

diff --cc fs/xfs/linux-2.6/xfs_aops.c
Simple merge

diff --cc fs/xfs/xfs_iomap.c
Simple merge

diff --cc fs/xfs/xfs_iomap.h
Simple merge