Repair KVM image distribution after disk_profile

- Commit to to disk profile to carry disk info
- repair mismatch between file cache copy, and DOM XML
- embed pool info in disk_profile.  Seems consistent with the profile
  goals
- added a return value of vm_info to init (it should return something
  useful, right!)
Merge pull request #7533 from ajithhub/virt_image_path_problem

Repair virt.init KVM image distribution after disk_profile