Fix for libvirt

Change-Id: Ie0083544246ccf1b53838d3c29722e629379972c
diff --git a/libvirt/server/single.yml b/libvirt/server/single.yml
index f25f8ed..dbf9177 100644
--- a/libvirt/server/single.yml
+++ b/libvirt/server/single.yml
@@ -1,3 +1,5 @@
+classes:
+- service.libvirt.server
 parameters:
   linux:
     system: