ext4: Convert more i_flags references to use accessor functions

These changes are not ones which are likely to result in races, but
they should be fixed.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

fs/ext4/migrate.c

@@ -376,7 +376,7 @@ static int ext4_ext_swap_inode_data(handle_t *handle, struct inode *inode,
 	 * We have the extent map build with the tmp inode.
 	 * Now copy the i_data across
 	 */
-	ei->i_flags |= EXT4_EXTENTS_FL;
+	ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS);
 	memcpy(ei->i_data, tmp_ei->i_data, sizeof(ei->i_data));
 
 	/*