Always disable use of libvirt wheel with UCA
Always disable use of libvirt wheel with UCA

It's not only using our upstream caches that you might get an old
libvirt-python wheel that is incompatible with UCA.  Move the ignore
out of the mirror check to apply it globally.

This is an alternative to Iba301a8c80c9ed584f5fb5a816f3d2cf5f5f0e77

Change-Id: I588b1e8e49aa60f3ce976dc1b6c8013ba1d88079

richliu/devstack,dtroyer/devstack,richliu/devstack,openstack-dev/devstack,noironetworks/devstack,dtroyer/devstack,noironetworks/devstack,group-policy/devstack,nawawi/openstack,nawawi/openstack,group-policy/devstack,openstack-dev/devstack