virsh: Wait until VM's are started before beginning quiesce
virsh: Wait until VM's are started before beginning quiesce

After the export, the VM startup is initiated, but virsh may
take some time to complete the start.

In this patch we introduce a wait until connectivity is
available before beginning the tasks in the quiesce process.

JIRA: OSP-12994

Change-Id: I41e0eed84a395cb3ee1aa998c97e965a5de9d111

redhat-openstack/infrared,redhat-openstack/infrared,redhat-openstack/infrared