start using available_features cfg option from tempest

[1] introduced a new list cfg option to tempest network-feature-enabled
available_features, which can list networking features without and
API extension.
As a first candidate ipv6_metadata can be added to master and victoria
jobs.

[1] https://review.opendev.org/760916

Change-Id: Ib8ba513ad098bb47d401ba64311b92280a85e1b2
diff --git a/zuul.d/ussuri_jobs.yaml b/zuul.d/ussuri_jobs.yaml
index 135d9f5..d04f5a0 100644
--- a/zuul.d/ussuri_jobs.yaml
+++ b/zuul.d/ussuri_jobs.yaml
@@ -82,9 +82,12 @@
         - uplink-status-propagation
       network_api_extensions_tempest:
         - dvr
+      network_available_features: &available_features
+        -
       devstack_localrc:
         NETWORK_API_EXTENSIONS: "{{ (network_api_extensions_common + network_api_extensions_tempest) | join(',') }}"
 
+
 - job:
     name: neutron-tempest-plugin-scenario-openvswitch-ussuri
     parent: neutron-tempest-plugin-scenario-openvswitch
@@ -93,14 +96,18 @@
     vars:
       branch_override: stable/ussuri
       network_api_extensions: *api_extensions
+      network_available_features: *available_features
       devstack_localrc:
         NETWORK_API_EXTENSIONS: "{{ network_api_extensions | join(',') }}"
       devstack_local_conf:
         test-config:
           $TEMPEST_CONFIG:
+            network-feature-enabled:
+              available_features: ""
             neutron_plugin_options:
               ipv6_metadata: False
 
+
 - job:
     name: neutron-tempest-plugin-scenario-openvswitch-iptables_hybrid-ussuri
     parent: neutron-tempest-plugin-scenario-openvswitch-iptables_hybrid
@@ -109,11 +116,14 @@
     vars:
       branch_override: stable/ussuri
       network_api_extensions: *api_extensions
+      network_available_features: *available_features
       devstack_localrc:
         NETWORK_API_EXTENSIONS: "{{ network_api_extensions | join(',') }}"
       devstack_local_conf:
         test-config:
           $TEMPEST_CONFIG:
+            network-feature-enabled:
+              available_features: ""
             neutron_plugin_options:
               ipv6_metadata: False
 
@@ -125,11 +135,14 @@
     vars:
       branch_override: stable/ussuri
       network_api_extensions: *api_extensions
+      network_available_features: *available_features
       devstack_localrc:
         NETWORK_API_EXTENSIONS: "{{ network_api_extensions | join(',') }}"
       devstack_local_conf:
         test-config:
           $TEMPEST_CONFIG:
+            network-feature-enabled:
+              available_features: ""
             neutron_plugin_options:
               ipv6_metadata: False