Fix missing mountpoint in glance bootstrap

Change-Id: I637eef710c0c4964a440e21e3ac15f8fca4b1830
Closes-Bug: #1519965

ansible/roles/glance/tasks/bootstrap.yml

@@ -47,7 +47,9 @@
     image: "{{ glance_api_image_full }}"
     name: "bootstrap_glance"
     restart_policy: "never"
-    volumes: "{{ node_config_directory }}/glance-api/:{{ container_config_directory }}/:ro"
+    volumes:
+      - "{{ node_config_directory }}/glance-api/:{{ container_config_directory }}/:ro"
+      - "glance:/var/lib/glance/"
   run_once: True
   delegate_to: "{{ groups['glance-api'][0] }}"
   when: database_created