Core/Loot: Fix master loot

Players will be able to open the loot window and see the items in case of master loot.
If the item is under threshold FFA applies, else the item becomes locked.

Also fix an exploit related to master loot item give.
Core/Loot: Implement round robin for under threshold items in case of master loot

Thanks @Shauren for pointing out
Merge pull request #11719 from Dehravor/master-loot

Core/Loot: Fix master loot