Remove unused variable (fixes warning)

src/handlers.c

@@ -648,7 +648,6 @@ int handle_windowname_change_legacy(void *data, xcb_connection_t *conn, uint8_t
 
         /* Save the old pointer to make the update atomic */
         char *new_name;
-        int new_len;
         asprintf(&new_name, "%.*s", xcb_get_property_value_length(prop), (char*)xcb_get_property_value(prop));
         /* Convert it to UCS-2 here for not having to convert it later every time we want to pass it to X */
         LOG("Name should change to \"%s\"\n", new_name);