Add XIV/DS8K volume driver to conf ref

This driver was refactored in Havana. The patch adds a short
stub reference, pulling in the existing table, and adds it in
to the list of volume drivers.

Change-Id: I6dd7bcd564d5c05f06a7932f1be7252b15993dc5
Closes-Bug: 1213605
Merge "Add XIV/DS8K volume driver to conf ref"