Core/maps: separate mutex for grid

src/server/game/Maps/Map.cpp

@@ -311,7 +311,7 @@ void Map::DeleteFromWorld(Player* player)
 
 void Map::EnsureGridCreated(const GridCoord &p)
 {
-    TRINITY_GUARD(ACE_Thread_Mutex, Lock);
+    TRINITY_GUARD(ACE_Thread_Mutex, GridLock);
     EnsureGridCreated_i(p);
 }
 

src/server/game/Maps/Map.h

@@ -526,6 +526,7 @@ class Map : public GridRefManager<NGridType>
         void SetUnloadReferenceLock(const GridCoord &p, bool on) { getNGrid(p.x_coord, p.y_coord)->setUnloadReferenceLock(on); }
 
         ACE_Thread_Mutex Lock;
+        ACE_Thread_Mutex GridLock;
 
         MapEntry const* i_mapEntry;
         uint8 i_spawnMode;