Fix Virtuozzo CI

Don't specify hypervisor_type=vz property for hds images as nova
now reports only really connected hypervisors and not all supported
by a compute host

Change-Id: Ibec0856519ffe593d44d123f3b401eae19f7d95a
diff --git a/functions b/functions
index f63595d..051c816 100644
--- a/functions
+++ b/functions
@@ -282,7 +282,6 @@
             image create \
             "$image_name" --public \
             --container-format=bare --disk-format=ploop \
-            --property hypervisor_type=vz \
             --property vm_mode=$vm_mode < "${image}"
         return
     fi