xfs: remove unused full argument from bmap

The "full" argument was used only by the fiemap formatter,
which is now gone with the iomap updates.

Remove the unused arg.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Alex Elder <elder@linaro.org>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>