scsi-disk: Inquiry with allocation length of CDB < 36 (v4)

scsi-disk: Inquiry with allocation length of CDB < 36 (v4)

According to the SCSI-2 specification,
http://ldkelley.com/SCSI2/SCSI2/SCSI2/SCSI2-08.html#8.2.5 ,
"if the allocation length of the command descriptor block (CDB) is too
small to transfer all of the parameters, the additional length shall
not be adjusted to reflect the truncation."
The 36 mandatory bytes of response are written to outbuf, and then
only the length requested in CDB is transferred.

Signed-off-by: Artyom Tarasenko <atar4qemu@gmail.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>