Fixes Hyper-V Inspector disk metrics bug

Changed disk metric names used by Hyper-V utils.

Was using wrong metric names before. 'Aggregated Disk Data Read/Written'
metrics refers to all disks (sum), while the metrics needs to be per disk.

Change-Id: I4ec36152a8b8147069151dd6eb98f36f7aab9229
Closes-Bug: 1250336
Merge "Fixes Hyper-V Inspector disk metrics bug"