MFC r198328: Add support for PIO-only devices. Fix maxio values and 256 sectors transactions for 28bits commands. Implement periodic ordered commands insertion, sames as da driver does. Remove some SCSIsms.
MFC r198328:
Add support for PIO-only devices.
Fix maxio values and 256 sectors transactions for 28bits commands.
Implement periodic ordered commands insertion, sames as da driver does.
Remove some SCSIsms.

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase