vc/slider: fix level mode range scaling
vc/slider: fix level mode range scaling

sbenejam/qlcplus,sbenejam/qlcplus,mcallegari/qlcplus,mcallegari/qlcplus,plugz/qlcplus,plugz/qlcplus,kripton/qlcplus,sbenejam/qlcplus,kripton/qlcplus,mcallegari/qlcplus,plugz/qlcplus,sbenejam/qlcplus,kripton/qlcplus,sbenejam/qlcplus,sbenejam/qlcplus,kripton/qlcplus,plugz/qlcplus,kripton/qlcplus,kripton/qlcplus,plugz/qlcplus,mcallegari/qlcplus,mcallegari/qlcplus,sbenejam/qlcplus,mcallegari/qlcplus,mcallegari/qlcplus,plugz/qlcplus,plugz/qlcplus,kripton/qlcplus