Core/Loot: fix bug introduced in a49544cc18 in which creatures only having gold wouldn't show lootable sparks, and thus couldn't be looted

(cherry picked from commit 59f71f915a)

src/server/game/Loot/LootMgr.cpp

@@ -816,6 +816,10 @@ uint32 Loot::GetMaxSlotInLootFor(Player* player) const
 // return true if there is any item that is lootable for any player (not quest item, FFA or conditional)
 bool Loot::hasItemForAll() const
 {
+    // Gold is always lootable
+    if (gold)
+        return true;
+
     for (LootItem const& item : items)
         if (!item.is_looted && !item.freeforall && item.conditions.empty())
             return true;