Remove Advanced section from screen config
Summary:
There was only one option hidden behind the andvanced section, just have
one line for refresh rate that is visible.
Reviewers: Plasma, VDG, ngraham
Reviewed By: VDG, ngraham
Subscribers: ngraham, andreaska, plasma-devel
Tags: Plasma
Differential Revision: https://phabricator.kde.org/D14325