Process initial lobby config while still at the loading screen

It's only intended to be used once, so no need to keep it around. Additionally, regardless of whether it's
processed here or in run_lobby_loop, it's no more up-to-date than at the point it was fetched.

src/game_initialization/multiplayer.cpp

@@ -399,12 +399,17 @@ class mp_manager
 		: game_config(&game_config_manager::get()->game_config())
 		, state(state)
 		, connection(nullptr)
-		, lobby_config()
 		, lobby_info(::installed_addons())
 	{
 		if(!host.empty()) {
 			gui2::dialogs::loading_screen::display([&]() {
+				config lobby_config;
 				std::tie(connection, lobby_config) = open_connection(host);
+
+				// Seed initial data
+				if(!lobby_config.empty()) {
+					lobby_info.process_gamelist(lobby_config);
+				}
 			});
 		}
 	}
@@ -422,11 +427,6 @@ class mp_manager
 			return;
 		}
 
-		// Seed initial data
-		if(!lobby_config.empty()) {
-			lobby_info.process_gamelist(lobby_config);
-		}
-
 		// A return of false means a config reload was requested, so do that and then loop.
 		while(!enter_lobby_mode()) {
 			game_config_manager* gcm = game_config_manager::get();
@@ -461,8 +461,6 @@ class mp_manager
 
 	std::unique_ptr<wesnothd_connection> connection;
 
-	config lobby_config;
-
 	mp::lobby_info lobby_info;
 };