Remove the Virtuozzo Storage Driver

The Virtuozzo Storage driver was marked
unsupported during the Train release.  Since
then, the 3rd Party CI hasn't been fixed and
there has been no sign of activity from the
vendor.  As a result the driver is being removed.

Change-Id: Ieb55bf4abed5856412576c3e45a5350c463deef2

cinder/opts.py

@@ -150,7 +150,6 @@
     cinder_volume_drivers_veritas_access_veritasiscsi
 from cinder.volume.drivers.vmware import vmdk as \
     cinder_volume_drivers_vmware_vmdk
-from cinder.volume.drivers import vzstorage as cinder_volume_drivers_vzstorage
 from cinder.volume.drivers.windows import iscsi as \
     cinder_volume_drivers_windows_iscsi
 from cinder.volume.drivers.windows import smbfs as \
@@ -350,7 +349,6 @@ def list_opts():
                 cinder_volume_drivers_stx_common.iscsi_opts,
                 cinder_volume_drivers_synology_synologycommon.cinder_opts,
                 cinder_volume_drivers_vmware_vmdk.vmdk_opts,
-                cinder_volume_drivers_vzstorage.vzstorage_opts,
                 cinder_volume_drivers_windows_iscsi.windows_opts,
                 cinder_volume_drivers_windows_smbfs.volume_opts,
                 cinder_volume_drivers_zadara.zadara_opts,