Pass region setting to identity

Since Queens oslo-templates get region from identity
section.

Change-Id: Id6b290f04efac1ae764ba7fa9d6221ece93898d3
Related-Prod: https://mirantis.jira.com/browse/PROD-21183
diff --git a/gnocchi/server/single.yml b/gnocchi/server/single.yml
index 035491e..32555cb 100644
--- a/gnocchi/server/single.yml
+++ b/gnocchi/server/single.yml
@@ -1,2 +1,7 @@
 classes:
 - service.gnocchi.server.single
+parameters:
+  gnocchi:
+    server:
+      identity:
+        region: ${_param:openstack_region}
\ No newline at end of file