https://bugzilla.redhat.com/show_bug.cgi?id=2070530
Version 1 was here:
https://listman.redhat.com/archives/libguestfs/2022-April/028560.html
Version 2 fixes the bogus mapping of source device names as pointed
out in Laszlo's review (and no longer touches target device names).
The rest of the patch is the same.
Rich.