Dungeon code cleanup

Consistent code, easier to read logic flow and some missing nullptr checks

src/strategy/dungeons/wotlk/hallsofstone/HallsOfStoneStrategy.cpp

@@ -26,4 +26,5 @@ void WotlkDungeonHoSStrategy::InitTriggers(std::vector<TriggerNode*> &triggers)
 void WotlkDungeonHoSStrategy::InitMultipliers(std::vector<Multiplier*> &multipliers)
 {
     multipliers.push_back(new KrystallusMultiplier(botAI));
+    multipliers.push_back(new SjonnirMultiplier(botAI));
 }