file: Don't call callback on every invalid rename

This was an error in [1] in which it's calling the passed callback
for every renaming failure, which was meant only for when the
entire operation ends. It was copied by mistake from the code for
single file rename operation.

[1] be12a75100

src/nautilus-file.c

@@ -2119,8 +2119,7 @@ real_batch_rename (GList                         *files,
 
         new_file_name = nautilus_file_can_rename_file (file,
                                                        new_name->str,
-                                                       callback,
-                                                       callback_data);
+                                                       NULL, NULL);
 
         if (new_file_name == NULL)
         {