IOS: Implement UID/GID changes for the PPC

This will be required for permission checks in the future.

Note that this is only for the PPC as we do not have actual processes.
Keeping track of other modules' UIDs/GIDs is virtually useless anyway.

UID/GID changes are implemented in the following functions:

* ES_Launch
* ES_DIVerify

ES_SetUid is not implemented yet because it'd need further changes.

Source/Core/DiscIO/NANDContentLoader.cpp

@@ -336,7 +336,7 @@ u64 CNANDContentManager::Install_WiiWAD(const std::string& filename)
   }
 
   IOS::ES::UIDSys uid_sys{Common::FromWhichRoot::FROM_CONFIGURED_ROOT};
-  uid_sys.AddTitle(title_id);
+  uid_sys.GetOrInsertUIDForTitle(title_id);
 
   ClearCache();