libxfs: fix whitespace problems

Fix some whitespace problems that trip up my libxfs-diff script.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>

fs/xfs/libxfs/xfs_rtbitmap.c

@@ -1016,4 +1016,3 @@ xfs_rtfree_extent(
 	}
 	return 0;
 }
-