This adds
      struct device_driver    gen_driver;
  
to ide_driver_t, which is filled in with necessary fields when an ide
driver calls ide_register_driver(). That then registers the driver with
the driver model core. 
  
As a result, this gives us the following output in driverfs:
  
# tree -d /sys/bus/ide/drivers/
/sys/bus/ide/drivers/
|-- ide-cdrom
`-- ide-disk
  
The suspend/resume callbacks in ide-disk.c have been temporarily
disabled until the ide core implements generic methods which forward
the calls to the drive drivers.