[RPi5] Update from LibreELEC 9.x to current

If it's a small library and you're planning to move content over from USB drive to the SSD it's probably easiest to move the content over and rescrape everything from the new location.

If it's a larger library and/you care about the watched status, the following /storage/.kodi/userdata content can be copied over:

• DB files
• sources.xml
• passwords.xml
• addon_data
• thumbnails

As the original /var/media/USBDRIVE path will have changed to /storage/videos/something you will need to use path substitution to map old paths to new ones, see https://kodi.wiki/view/Path_substitution

NB: No add-ons can be copied over as LE9 uses Python2 and we switched to Python3 since then.