libvirt: fix ivs test to use the ivs vif object
libvirt: fix ivs test to use the ivs vif object

One of the ivs vif tests was mistakenly using the vif_ovs object.
The test still worked by pure luck.

Change-Id: I74fca7653d4103a62828fc3a5991dd192f731f21

Juniper/nova,mikalstill/nova,openstack/nova,rahulunair/nova,mahak/nova,cernops/nova,gooddata/openstack-nova,phenoxim/nova,gooddata/openstack-nova,Juniper/nova,zhimin711/nova,klmitch/nova,cernops/nova,bigswitch/nova,jianghuaw/nova,jianghuaw/nova,klmitch/nova,Juniper/nova,openstack/nova,vmturbo/nova,sebrandon1/nova,cloudbase/nova,klmitch/nova,phenoxim/nova,rahulunair/nova,gooddata/openstack-nova,vmturbo/nova,hanlind/nova,sebrandon1/nova,vmturbo/nova,bigswitch/nova,rahulunair/nova,jianghuaw/nova,rajalokan/nova,vmturbo/nova,hanlind/nova,jianghuaw/nova,rajalokan/nova,mikalstill/nova,zhimin711/nova,cloudbase/nova,mahak/nova,sebrandon1/nova,hanlind/nova,rajalokan/nova,cernops/nova,openstack/nova,mahak/nova,mikalstill/nova,alaski/nova,cloudbase/nova,alaski/nova,klmitch/nova,gooddata/openstack-nova,rajalokan/nova,Juniper/nova