Add openstack_node_role parameter

Add openstack_node_role parameter that will specify node role
primary|secondary. This metadata will be used by formulas as a
trigger to run one-shot operations.

Change-Id: I230590bc5f9d53960c6edaf7e37c44541d9c3342
Related-Prod: PROD-21267
diff --git a/gnocchi/server/single.yml b/gnocchi/server/single.yml
index d82dfee..11ddf39 100644
--- a/gnocchi/server/single.yml
+++ b/gnocchi/server/single.yml
@@ -3,6 +3,7 @@
 parameters:
   gnocchi:
     server:
+      role: ${_param:openstack_node_role}
       identity:
         region: ${_param:openstack_region}
       metricd: