look-and-feel: Move settings from plasma-phone-settings to defaults

See teams/plasma-mobile/issues#148

Haven't tested it yet, and I believe that some settings might not apply, have to investigate the whitelist in https://invent.kde.org/plasma/plasma-workspace/-/blob/master/kcms/lookandfeel/lookandfeelmanager.cpp

CC: @apol @mart @bshah