Staging: hv: storvsc: Miscellaneous cleanup of storvsc driver

Miscellaneous cleanup of storvsc driver - get rid of unnecessary defines and
use fixed size types for structures used for communication with the host.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>