Improve inventory scoping for limited play execution

When executing the playbook with limits set, the scoping
currently does not work quite as well as one would hope.

This tightens it a bit more to ensure that it operates
as expected.

Change-Id: I8ebd42bcdf9676fd580955256498bbd8801f1cbd

handlers/main.yml

@@ -71,7 +71,7 @@
   when:
     - "ansible_local['openstack_ansible']['neutron']['need_db_contract'] | bool"
     - "neutron_services['neutron-server']['group'] in group_names"
-    - "inventory_hostname == ansible_play_hosts[0]"
+    - "inventory_hostname == (groups[neutron_services['neutron-server']['group']] | intersect(ansible_play_hosts))[0]"
   listen: "Restart neutron services"
 
 - name: Start services

tasks/main.yml

@@ -96,7 +96,7 @@
   static: no
   when:
     - "neutron_services['neutron-server']['group'] in group_names"
-    - "inventory_hostname == ansible_play_hosts[0]"
+    - "inventory_hostname == (groups[neutron_services['neutron-server']['group']] | intersect(ansible_play_hosts))[0]"
   tags:
     - neutron-config
 

tasks/neutron_db_setup.yml

@@ -19,7 +19,7 @@
   become_user: "{{ neutron_system_user_name }}"
   when:
     - "ansible_local['openstack_ansible']['neutron']['need_db_expand'] | bool"
-    - "inventory_hostname == ansible_play_hosts[0]"
+    - "inventory_hostname == (groups[neutron_services['neutron-server']['group']] | intersect(ansible_play_hosts))[0]"
 
 - name: Disable the db expand fact
   ini_file:
@@ -33,7 +33,7 @@
   become: yes
   become_user: "{{ neutron_system_user_name }}"
   when:
-    - "inventory_hostname == ansible_play_hosts[0]"
+    - "inventory_hostname == (groups[neutron_services['neutron-server']['group']] | intersect(ansible_play_hosts))[0]"
   changed_when: false
   register: _offline_migrations_check
   failed_when: