CLOUDSTACK-7494. Migration of a vm fails on Hyper-V. In an earlier commit as part of
cleaning up vmsync changes, checkvirtualmachine command was updated to return the
power state of the vm. The change was missed for Hyper-V. This caused migration to
fail on cloudstack even though it used to succeed on the hypervisor. Updated the
hyper-v agent code to return the cloudstack equivalent power state for check virtual
machine answer.