Explicitly pull chkconfig into live images
As livesys and livesys-late are still SysV services, they need
systemd-sysv-install to work, which is part of chkconfig. Until
now chkconfig was getting pulled into live images via packages
that require update-alternatives, which was previously part of
chkconfig - but it just got split into its own package, so now
those packages don't pull in chkconfig any more.
This broke the KDE live image and probably several others in
recent Rawhide, livesys and livesys-late don't run so there's
no 'liveuser' and root isn't accessible. Workstation didn't
break because a java package still pulls chkconfig into it.
Signed-off-by: Adam Williamson <awilliam@redhat.com>