[Merge] ~xnox/livecd-rootfs:preinstalled into livecd-rootfs:ubuntu/master

[Dimitri John Ledkov]

Tested that all this works correctly with amd64 and arm64.
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https://code.launchpad.net/~xnox/livecd-rootfs/+git/livecd-rootfs/+merge/401222
Your team Ubuntu Core Development Team is requested to review the proposed merge of ~xnox/livecd-rootfs:preinstalled into livecd-rootfs:ubuntu/master.