Core: Pass by const reference for simple objects replaced with pass by value

src/server/game/Maps/MapInstanced.cpp

@@ -44,7 +44,7 @@ void MapInstanced::InitVisibilityDistance()
     }
 }
 
-void MapInstanced::Update(const uint32& t)
+void MapInstanced::Update(const uint32 t)
 {
     // take care of loaded GridMaps (when unused, unload it!)
     Map::Update(t);