Add neutron metadata for memcache security strategy

Related-Prod: PROD-22099 (PROD:22099)

Change-Id: I3371c13c2f581521bc57029a186770997c49d0f2
diff --git a/neutron/gateway/cluster.yml b/neutron/gateway/cluster.yml
index 8f84fa1..bc51ab9 100644
--- a/neutron/gateway/cluster.yml
+++ b/neutron/gateway/cluster.yml
@@ -31,3 +31,8 @@
           cert_file: ${_param:rabbitmq_neutron_client_ssl_cert_file}
         ssl:
           enabled: ${_param:rabbitmq_ssl_enabled}
+      cache:
+        security:
+          enabled: ${_param:neutron_memcache_security_enabled}
+          strategy: ${_param:openstack_memcache_security_strategy}
+          secret_key: ${_param:neutron_memcache_secret_key}