scsi: storvsc: Add ability to change scsi queue depth

Adding functionality to allow the SCSI queue depth to be changed by
utilizing the "scsi_change_queue_depth" function.

[mkp: checkpatch]

Signed-off-by: Branden Bonaby <brandonbonaby94@gmail.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Reviewed-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>