Add a check for controllers without ironic enabled

ansible/kolla-openstack.yml

 ---
+
+- name: Ensure Ironic is enabled
+  hosts: controllers
+  tasks:
+    - name: Create controllers group with ironic enabled
+      group_by:
+        key: "controllers_with_ironic_enabled_{{ kolla_enable_ironic }}"
+
 - name: Ensure locally built Ironic Python Agent images are copied
-  hosts: controllers[0]
+  hosts: controllers_with_ironic_enabled_True
   vars:
     # These are the filenames generated by overcloud-ipa-build.yml.
     ipa_image_name: "ipa"