(currently only CD-ROM drives on i386). The sys/dev/scsipi system provides 2
busses to which devices can attach (scsibus and atapibus). This needed to
change some include files and structure names in the low level scsi drivers.
bits that tell the driver not to expect parity from those targets.
XXX: For now, it is up to MD code to set this mask. Eventually,
XXX: we should identify targets first (without demanding parity)
XXX: and then use a new "SCSI quirk" to set the right bit.