Fix default nova node names in Grizzly

Folsom compute node names are unqualified in the database, Grizzly
qualifies them with the value of dhcp_domain.  In the migration
we'll unset that for now.

Bug 1160072

Change-Id: I176cace9c5319265944c276d5c8eae704e99f671
Merge "Fix default nova node names in Grizzly"