Revert focus policy change in tab_game

Fixes #1529.

Completely untested, because I don't think this could possibly interfere with anything. It's a straight revert.

cockatrice/src/tab_game.cpp

@@ -452,7 +452,6 @@ TabGame::TabGame(TabSupervisor *_tabSupervisor, QList<AbstractClient *> &_client
     scene = new GameScene(phasesToolbar, this);
     gameView = new GameView(scene);
     gameView->hide();
-    gameView->setFocusPolicy(Qt::ClickFocus);
     
     cardInfo = new CardFrame();
     playerListWidget = new PlayerListWidget(tabSupervisor, clients.first(), this);