This is necessary for the eventual removal of SCp from struct scsi_cmnd.

Link: https://lore.kernel.org/r/20220218195117.25689-9-bvanassche@acm.org
Cc: Michael Schmitz <schmitzmic@gmail.com>
Cc: Ondrej Zary <linux@zary.sk>
Suggested-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Finn Thain <fthain@linux-m68k.org>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>