Fixes get_vm_storage_paths issue for Hyper-V V2 API

Add get_vm_storage_paths function to vmutilsv2.py

get_vm_storage_paths implementation on Hyper-V V2 API changed
compared to previous V1 API. In previous V1 APIs, using
Msvm_ResourceAllocationSettingData class can get storage
paths, but in V2 API, only using Msvm_StorageAllocationSettingData
class can get the storage paths.

Closes-Bug: #1248463

Change-Id: Ica73221524f162a6ffcd9dc64ee33c85fb5ad31d