Install Octavia amphora image if Red Hat

For a one-click deployment, the Octavia amphora image must be present in
the undercloud node. Currently users need to ensure the image file
exists before overcloud deployment. For Red Hat-based deployments, the
image is provided by package octavia-amphora-image. Thus the package
should be installed for a better user experience leading to a truly
one-click deployment.

Closes-Bug: #1770117
Change-Id: I3ed8144b52ba528f449a4abe5c2106a5c61f9d61

playbooks/roles/octavia-undercloud/tasks/main.yml

@@ -9,9 +9,14 @@
       image_filename: "/usr/share/openstack-octavia-amphora-images/amphora-x64-haproxy.qcow2"
     when: ansible_distribution == 'CentOS' and not image_filename is defined
 
-  - name: set location if Red Hat
-    set_fact:
-      image_filename: "/usr/share/rhosp-director-images/octavia-amphora.qcow2"
+  - block:
+      - name: install Octavia amphora image if Red Hat
+        yum:
+          name: octavia-amphora-image
+          state: latest
+      - name: set location if Red Hat
+        set_fact:
+          image_filename: "/usr/share/rhosp-director-images/octavia-amphora.qcow2"
     when: ansible_distribution == 'RedHat' and not image_filename is defined
 
   - name: check if amphora image file exists

releasenotes/notes/install-octavia-amphora-image-red-hat-bc8545e36d88f951.yaml

@@ -0,0 +1,3 @@
+---
+features:
+  - Install Octavia amphora image on the undercloud if Red Hat.