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/aodh/server/single.yml b/aodh/server/single.yml
index df4be81..6eec70e 100644
--- a/aodh/server/single.yml
+++ b/aodh/server/single.yml
@@ -5,4 +5,7 @@
     openstack_event_alarm_topic: alarm.all
   aodh:
     server:
+      region: ${_param:openstack_region}
       event_alarm_topic: ${_param:openstack_event_alarm_topic}
+      identity:
+        region: ${_param:openstack_region}