scsi: NCR5380: Remove the NCR5380_CMD_SIZE macro

scsi: NCR5380: Remove the NCR5380_CMD_SIZE macro

This makes it easier to find users of the NCR5380_cmd data structure with
'grep'.

Link: https://lore.kernel.org/r/20220218195117.25689-8-bvanassche@acm.org
Cc: Finn Thain <fthain@telegraphics.com.au>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Ondrej Zary <linux@rainbow-software.org>
Cc: Michael Schmitz <schmitzmic@gmail.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-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>