Fix init script so it compatible with newer systemd versions
Fix init script so it compatible with newer systemd versions

Change-Id: I77adfb2b5e328f29e701b8d29c5b4319617d2ecb

sapcc/monasca-thresh,openstack/monasca-thresh,stackforge/monasca-thresh,stackforge/monasca-thresh,openstack/monasca-thresh,sapcc/monasca-thresh,openstack/monasca-thresh