CLOUDSTACK-6830: Fixed [hyper-v] during VM migration, volumes on zone wide primary
store requires storage migration resulting in failure of VM migration. This also
improves the hostsformigration api. Firstly we were trying to list all hosts and
then finding suitable storage pools for all volumes and then we were checking
whether vm migration requires storage migration to that host. Now the process is
updated. We are checking for only those volumes which are not in zone wide primary
store. We are verifying by comparing volumes->poolid->clusterid to host clusterid.
If it uses local or clusterids are different then verifying whether host has
suitable storage pools for the volume of the vm to be migrated too.