Fixes Hyper-V agent IDE/SCSI related refactoring

Hyper-V Server 2012 R2 introduces a new feature for virtual
machines named "generation 2".

Generation 2 VMs don't support IDE devices, meaning that VHDs
and DVD Drives must be attached as SCSI, instead of IDE.

Since the Virtual Hard Disks and Virtual CD/DVD Disks can be
attached to IDE controllers or SCSI controllers (generation 2
only), some constants, variables and methods have been
improperly named, having the IDE prefix.

Partially implements: blueprint hyper-v-generation-2-vms

Change-Id: Ic281d7548dfe6b2f65290f687ea0ca694db1a4d0
Merge "Fixes Hyper-V agent IDE/SCSI related refactoring"