- Kill unneded parameters to ide_cmd_ioctl() and ide_task_ioctl().

- Apply Petr Vendrovecs fix for 32bit ver 16bit transfers.

- Make CD-ROM usable again by guarding the generic routines against request
   field abuse found there. We will try to convert this driver to the just to be
   finished struct ata_request after the generic changes stabilize a bit.
   The strcut ata_taskfile and struct ata_request merge to be more preciese.