xfs: remove unused tp arg from xfs_bmap_last_offset() and callers

remove unused transaction pointer from various
callchains leading to xfs_bmap_last_offset().

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>

diff --git a/fs/xfs/xfs_dir2_leaf.c b/fs/xfs/xfs_dir2_leaf.c
index d36e97d..f571723 100644
--- a/fs/xfs/xfs_dir2_leaf.c
+++ b/fs/xfs/xfs_dir2_leaf.c
@@ -1708,7 +1708,7 @@
 	/*
 	 * Get the last offset in the file.
 	 */
-	if ((error = xfs_bmap_last_offset(tp, dp, &fo, XFS_DATA_FORK))) {
+	if ((error = xfs_bmap_last_offset(dp, &fo, XFS_DATA_FORK))) {
 		return error;
 	}
 	fo -= mp->m_dirblkfsbs;