Somehow the part that enables and disabled this quicksetting got lost
while everything needed is in place. So add it, which fixes showing and
hiding this quicksettings button.
Signed-off-by: Sebastian Kügler <sebas@kde.org>
This quicksetting plugion allows the user to open the KScreen OSD which
makes it easy to reconfigure a multiscreen setup. It's only available
when more than one monitor is connected.
Signed-off-by: Sebastian Kügler <sebas@kde.org>