purge-cluster: remove support for other init system
purge-cluster: remove support for other init system

We only support systemd and use the service module anyway.

Signed-off-by: Sébastien Han <62d754cc350e84d3b1c32ae79f976f5348e74a40@redhat.com>

ceph/ceph-ansible,ceph/ceph-ansible,fgal/ceph-ansible,fgal/ceph-ansible