Core/Vehicles:

- Grab correct npc entry from npc_spellclick_spells in case of player vehicle. Fixes DB errors added in my previous changeset
- Allow aura's with SPELL_AURA_CONTROL_VEHICLE to stack if there are enough free seats, even if spellIds are identical.
- Fix a possible infinite loop. Thanks to manuel for spotting

src/server/game/Entities/Unit/Unit.h

@@ -2039,7 +2039,7 @@ class Unit : public WorldObject
         Unit *GetMisdirectionTarget() { return m_misdirectionTargetGUID ? GetUnit(*this, m_misdirectionTargetGUID) : NULL; }
 
         bool IsAIEnabled, NeedChangeAI;
-        bool CreateVehicleKit(uint32 id);
+        bool CreateVehicleKit(uint32 id, uint32 creatureEntry);
         void RemoveVehicleKit();
         Vehicle *GetVehicleKit()const { return m_vehicleKit; }
         Vehicle *GetVehicle()   const { return m_vehicle; }