Update nova memcache defaults

Change-Id: Ia88107057d0e8a05f4734f43ed71044dc6f1b369
diff --git a/defaults/openstack/init.yml b/defaults/openstack/init.yml
index 49ad5c6..e0d808c 100644
--- a/defaults/openstack/init.yml
+++ b/defaults/openstack/init.yml
@@ -15,3 +15,6 @@
     # Cinder
     cinder_memcache_security_enabled: ${_param:openstack_memcache_security_enabled}
     cinder_memcache_secret_key: ''
+    # Nova
+    nova_memcache_security_enabled: ${_param:openstack_memcache_security_enabled}
+    nova_memcache_secret_key: ''