Add /root/.cache/image-create to cleanup role

This commit clears the DIB cache on virthosts used in rdophase2.

Change-Id: I6b77d1b0f11d7240179f67cca6a84e7909d3fd20

roles/virthost-full-cleanup/tasks/main.yml

@@ -42,6 +42,7 @@
         rm -rf /var/log/artib;
         rm -rf /home/oooq-images;
         rm -rf /var/lib/oooq-images;
+        rm -rf /root/.cache/image-create;
 
     - name: destroy brbm network
       command: virsh net-destroy brbm