xfs: replace inode fork size macros with functions

Replace the shouty macros here with typechecked helper functions.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
diff --git a/fs/xfs/libxfs/xfs_attr_leaf.c b/fs/xfs/libxfs/xfs_attr_leaf.c
index 435c6cc..5bd554b 100644
--- a/fs/xfs/libxfs/xfs_attr_leaf.c
+++ b/fs/xfs/libxfs/xfs_attr_leaf.c
@@ -590,7 +590,7 @@ xfs_attr_shortform_bytesfit(
 	 * to real extents, or the delalloc conversion will take care of the
 	 * literal area rebalancing.
 	 */
-	if (bytes <= XFS_IFORK_ASIZE(dp))
+	if (bytes <= xfs_inode_attr_fork_size(dp))
 		return dp->i_forkoff;
 
 	/*