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/victoria_jobs.yaml b/zuul.d/victoria_jobs.yaml
index 0bc1e13..78956ad 100644
--- a/zuul.d/victoria_jobs.yaml
+++ b/zuul.d/victoria_jobs.yaml
@@ -81,6 +81,8 @@
         - uplink-status-propagation
       network_api_extensions_tempest:
         - dvr
+      network_available_features: &available_features
+        - ipv6_metadata
       devstack_localrc:
         NETWORK_API_EXTENSIONS: "{{ (network_api_extensions_common + network_api_extensions_tempest) | join(',') }}"
 
@@ -91,11 +93,14 @@
     vars:
       branch_override: stable/victoria
       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: "{{ network_available_features | join(',') }}"
             neutron_plugin_options:
               ipv6_metadata: False
 
@@ -106,11 +111,14 @@
     vars:
       branch_override: stable-victoria
       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: "{{ network_available_features | join(',') }}"
             neutron_plugin_options:
               ipv6_metadata: False
 
@@ -121,11 +129,14 @@
     vars:
       branch_override: stable/victoria
       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: "{{ network_available_features | join(',') }}"
             neutron_plugin_options:
               ipv6_metadata: False
 
@@ -138,6 +149,11 @@
       network_api_extensions: *api_extensions
       devstack_localrc:
         NETWORK_API_EXTENSIONS: "{{ network_api_extensions | join(',') }}"
+      devstack_local_conf:
+        test-config:
+          $TEMPEST_CONFIG:
+            network-feature-enabled:
+              available_features: ""
 
 - job:
     name: neutron-tempest-plugin-dvr-multinode-scenario-victoria