Hyper-V provides options to specify maximum IOPS per virtual disk
image.
By leveraging this feature, this blueprint proposes to add support
for setting QoS specs targeting instance local disks as well
as volumes exported through SMB.
This will work similar to the libvirt driver, expecting the same
extra specs.
Implements: blueprint hyperv-storage-qos
Change-Id: I4ce44c8b7ab54a0bfc8c7401e675876dbd109e2d