[SCSI] storvsc: Account for in-transit packets in the RESET path

Properly account for I/O in transit before returning from the RESET call.
In the absense of this patch, we could have a situation where the host may
respond to a command that was issued prior to the issuance of the RESET
command at some arbitrary time after responding to the RESET command.
Currently, the host does not do anything with the RESET command.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: stable@vger.kernel.org
Signed-off-by: James Bottomley <JBottomley@Parallels.com>