Allowing users to manually change the font DPI independent of font sizes
and the global scale is already of questionable value on X11, but on
Wayland where Qt scaling is always used, it is an anachronism. So let's
only show it on X11. On Wayland, people can use the global scaling
feature in the KScreen KCM.
See also https://phabricator.kde.org/T9500
We currently need the lookandfeel and style kcm in plasma-workspace, but
appearantly they depend on the krdb so best solution is to move all kcms
together
They are taken from plasma-desktop at the commit :
8447c08e878ccbde9c5516ba8a912993ea199cb9