Fix using town map as registered item (#7482)

src/item_use.c

@@ -1609,8 +1609,7 @@ void ItemUseOutOfBattle_TownMap(u8 taskId)
     }
     else
     {
-        // TODO: handle key items with callbacks to menus allow to be used by registering them.
-        DisplayDadsAdviceCannotUseItemMessage(taskId, gTasks[taskId].tUsingRegisteredKeyItem);
+        gTasks[taskId].func = ItemUseOnFieldCB_TownMap;
     }
 }