This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.
Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.
Reenabled "SCIOCOMAND" ioctl.
Restructured so low level drivers can easily request retries.
Added preliminary fixed SCSI devices (should be revisited before 2.1)
Added "ssc" device that can have its' (HBA, ID, LUN) set via ioctl.