Migrate building IPA to ironic-python-agent-builder

We're switching the building process to a new project that is governed
and supported by the ironic team.

Change-Id: Ib05ccaaddad105c27024ca5ee4d8ca0a0452bddf

heat_docker_agent/configure_container.sh

@@ -48,6 +48,7 @@ yum install -y \
         initscripts \
         jq \
         puppet-tripleo \
+        openstack-ironic-python-agent-builder \
         openstack-tripleo-image-elements \
         openstack-tripleo-puppet-elements \
         openvswitch \

image-yaml/overcloud-images.yaml

@@ -44,7 +44,7 @@ disk_images:
     # So we just override the extension instead
     imageext: initramfs
     elements:
-      - ironic-agent
+      - ironic-python-agent-ramdisk
       - ironic-agent-multipath
       - dynamic-login
       - element-manifest

tripleo_common/image/image_builder.py

@@ -82,6 +82,7 @@ class DibImageBuilder(ImageBuilder):
             env['ELEMENTS_PATH'] = os.pathsep.join([
                 "/usr/share/tripleo-puppet-elements",
                 '/usr/share/tripleo-image-elements',
+                '/usr/share/ironic-python-agent-builder/dib',
             ])
             os.environ.update(env)