Currently volume list supports most of the filters since it
directly passes filter parameters to bottom pods. But
availability zone filter can not be implememted like that
because we don't require top pod and bottom pod to have
availability zones with the same name. Since each bottom pod
belongs to an availability zone defined in top pod, instead
of passing the availability zone filter to bottom pods, we
directly filter bottom pods by the availability zone filter
then send list request to these filtered bottom pods.
With change in this patch, tempest test test_volumes_list can
be passed.
Change-Id: I8e448a1262ca370ff3bfa9948fee636240a7fb78
fa9db37e64