Add debug logs when doubling-up allocations during scheduling
Add debug logs when doubling-up allocations during scheduling

During claim_resources in the scheduler, if the consumer (instance)
has existing allocations, the scheduler thinks we're doing something
like a resize to same host or evacuation, but it would be useful
to know what the original allocations when doing that, so this adds
logging of the original allocations that take us down the double-up
path.

Change-Id: Ibfb0e97840141a4d60701f8c938fedad0fc4c758
Related-Bug: #1798688

rahulunair/nova,mahak/nova,klmitch/nova,openstack/nova,rahulunair/nova,mahak/nova,mikalstill/nova,openstack/nova,mikalstill/nova,klmitch/nova,mahak/nova,klmitch/nova,rahulunair/nova,klmitch/nova,mikalstill/nova,openstack/nova