UBIFS: use __aligned() attribute

.. instead of __attribute__((aligned())).
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>

fs/ubifs/commit.c

@@ -514,7 +514,7 @@ struct idx_node {
 	struct list_head list;
 	int iip;
 	union ubifs_key upper_key;
-	struct ubifs_idx_node idx __attribute__((aligned(8)));
+	struct ubifs_idx_node idx __aligned(8);
 };
 
 /**