Volumes tabs should be enabled when volumev2 endpoint is registered.
Currently, Horizon considers no volume service is running if there
is no V1 endpoint, which doesn't make sense as Horizon no longer
supports the cinder V1 protocol.
Co-Authored-By: itxaka <itxaka@redhat.com>
Change-Id: I35d821eedb75f73f9330ed11f921694104eed0c6
Closes-Bug: 1415712
2e59431227