Build placement images by default

placement has been split from nova, see:

2f657085c6 (diff-c5172145fe90316d5c16e60e61a592a2)

Change-Id: Icf54da6a0d1439fc416b556707a62df300daa9bf
Story: 2006248
Task: 35857

ansible/group_vars/all/kolla

@@ -193,6 +193,8 @@ overcloud_container_image_regex_map:
     enabled: "{{ kolla_enable_neutron | bool }}"
   - regex: rabbitmq
     enabled: True
+  - regex: placement
+    enabled: "{{ kolla_enable_nova | bool }}"
   - regex: prometheus
     enabled: "{{ kolla_enable_prometheus | bool }}"
   - regex: sahara