Remove unused nova packages from host during upgrade and update

As of now, during to upgrade from pike -> queens or doing
minor update on pike/queens deployment, the nova packages upgrade
on compute node changes the permissions on /var/lib/nova tree from
42436 (container nova uid) to 162 (host nova uid) which
prevents user from creating instances with permission Error.

This change handles removing unused nova packages from compute
host during major upgrade as well as minor update on explicitly.

Change-Id: I7e7167252f08f5df555912e0692f33649228fc83

docker/services/nova-compute.yaml

@@ -50,10 +50,6 @@ parameters:
     description: Port that dockerized nova migration target sshd service
                  binds to.
     type: number
-  UpgradeRemoveUnusedPackages:
-    default: false
-    description: Remove package if the service is being disabled during upgrade
-    type: boolean
   CephClientUserName:
     default: openstack
     type: string
@@ -286,15 +282,21 @@ outputs:
               file: path=/var/lib/nova/instanceha/enabled state=touch
               when: iha_nodes.stdout|lower | search('"'+ansible_hostname|lower+'"')
       upgrade_tasks:
-        - when: step|int == 2
-          block:
-            - name: Set fact for removal of openstack-nova-compute package
-              set_fact:
-                remove_nova_compute_package: {get_param: UpgradeRemoveUnusedPackages}
-            - name: Remove openstack-nova-compute package if operator requests it
-              package: name=openstack-nova-compute state=removed
-              ignore_errors: True
-              when: remove_nova_compute_package|bool
+        - name: Remove openstack-nova-compute and python-nova package during upgrade
+          package: name={{ item }} state=removed
+          with_items:
+            - openstack-nova-compute
+            - python-nova
+          ignore_errors: True
+          when: step|int == 2
+      update_tasks:
+        - name: Remove openstack-nova-compute and python-nova package during update
+          package: name={{ item }} state=removed
+          with_items:
+            - openstack-nova-compute
+            - python-nova
+          ignore_errors: True
+          when: step|int == 2
       post_upgrade_tasks:
         - when: step|int == 1
           import_role: