Core/Units: Allow mind controlling non-controllable vehicles (for example players that become vehicle during boss encounters or creatures that only are vehicles to show non standard power type)

Port From (https://github.com/TrinityCore/TrinityCore/commit/d56d92fbe7436af00e00b00ca5e7640f852d3485)

Source/Game/Entities/Vehicle.cs

@@ -434,6 +434,15 @@ namespace Game.Entities
             return false;
         }
 
+        public bool IsControllableVehicle()
+        {
+            foreach (var itr in Seats)
+                if (itr.Value.SeatInfo.HasFlag(VehicleSeatFlags.CanControl))
+                    return true;
+
+            return false;
+        }
+        
         void InitMovementInfoForBase()
         {
             VehicleFlags vehicleFlags = (VehicleFlags)GetVehicleInfo().Flags;