Added scale_tasks to handle cleanup on scale down of nodes

scale_down tasks will be executed when a node is scaled down to
deregister the node with ipa and clean up the relevant subhosts and
services and revoke the issued certs.

Change-Id: Ib636dc528687dc67fae85c27a1571f51ae7332e7

deployment/ipa/ipaservices-baremetal-ansible.yaml

@@ -88,8 +88,8 @@ outputs:
             vars:
               tripleo_ipa_enroll_base_server: {get_param: IdMEnrollBaseServer}
               tripleo_ipa_delegate_server: "{{ item }}"
-              tripleo_ipa_base_server_fqdn:  "{{hostvars[item]['fqdn_canonical']}}"
-              tripleo_ipa_server_metadata: "{{hostvars[item]['service_metadata_settings'] | to_json }}"
+              tripleo_ipa_base_server_fqdn:  "{{ hostvars[item]['fqdn_canonical'] }}"
+              tripleo_ipa_server_metadata: "{{ hostvars[item]['service_metadata_settings'] | to_json }}"
             loop: "{{ groups.certmonger_user }}"
           - include_role:
               name: tripleo_ipa_dns
@@ -132,3 +132,15 @@ outputs:
             when:
             - idm_enroll_base_server|bool
             - not ipa_conf_exists.stat.exists
+      scale_tasks:
+        - when: step|int == 1
+          tags: down
+          block:
+            - name: unregister node from ipa server
+              import_role:
+                name: tripleo_ipa_cleanup
+              delegate_to: localhost
+              vars:
+                tripleo_ipa_keytab: {get_param: IdMNovaKeytab}
+                tripleo_ipa_hosts_to_delete:
+                  - "{{ fqdn_canonical }}"