Remove KDevicePropsPlugin from KPropertiesDialog
It mainly handled device .desktop files (the Create New -> "link to device" context menu entry):
- That "link to device" template file hasn't been installed in a long time
- It was used to mount CDROM drives (which is handled by UDisks anyway nowadays so it'll show up automatically in the Places panel and the Device Notifier in the system tray) and Floppy drives, USB sticks have replaced both those types of media
For more details, see the comments in this KF6 task: https://phabricator.kde.org/T14295