hyperv: Fixes log message in livemigrationops
hyperv: Fixes log message in livemigrationops

The instance should be passed as key-value argument to the
logger.

Change-Id: Id59f709a0c40dccdc75212816f97298cd9a6d521
Closes-Bug: #1701511

Juniper/nova,vmturbo/nova,gooddata/openstack-nova,jianghuaw/nova,mikalstill/nova,gooddata/openstack-nova,klmitch/nova,gooddata/openstack-nova,vmturbo/nova,openstack/nova,mikalstill/nova,openstack/nova,klmitch/nova,klmitch/nova,mahak/nova,gooddata/openstack-nova,Juniper/nova,jianghuaw/nova,jianghuaw/nova,vmturbo/nova,rahulunair/nova,mikalstill/nova,rahulunair/nova,rahulunair/nova,Juniper/nova,openstack/nova,klmitch/nova,vmturbo/nova,phenoxim/nova,jianghuaw/nova,phenoxim/nova,Juniper/nova,mahak/nova,mahak/nova