scsi: core: reshuffle no_scsi2_lun_in_cdb for better alignment

no_scsi2_lun_in_cdb declares a new bitfield, but we should rather move
it to the existing bitfield for better alignment.

Signed-off-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>