libata: Support for an ATA PASS-THROUGH(32) command.

SAT-4(SCSI/ATA Translation) supports for an ata pass-thru(32).
This patch will allow to translate an ata pass-thru(32) SCSI cmd
to an ATA cmd.

Signed-off-by: Minwoo Im <dn3108@gmail.com>
Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Tejun Heo <tj@kernel.org>