outputconfigurationstore: split user configured and automatically set modes
If the mode the user has previously set through KScreen isn't available, this falls back to a different mode without overwriting the user preference. If on the next hotplug, the desired mode is available again, it then gets chosen instead of the fallback
(cherry picked from commit 8c257840)
Co-authored-by: Xaver Hugl xaver.hugl@gmail.com