Since Fedora 30, license files are missing from the ISO filesystem
of live or installer images (including official builds). The source
path to these files changed when they were moved into a subpackage
named fedora-release-common (or generic-release-common).
Also, copy the license files from the installroot, rather than the
existing root filesystem.
(cherry picked from commit 7df94aed4d)
xorrisofs needs to use iso-level 3 when creating images with large
files. This adds tests to all the relevant templates, just like we used
to do for udf and mkisofs.
