Disk images are usually flashed to media which is much larger
than they are, and all that additional space goes unused until
the user intervenes.
Configure things so that systemd-repart, which runs by default,
automatically takes care of resizing the root partition.
systemd-growfs, which also runs by default, will subsequently
take care of resizing the filesystem to fill the newly-enlarged
partition.
Note that we don't do this for cloud images, since in that
case cloud-init takes care of resizing the root filesystem and
the underlying partition together with all the other setup
tasks.
Signed-off-by: Andrea Bolognani <abologna@redhat.com>
