- Finally unify task_in_intr and task_mulin_intr. One crucial code path less to
   watch out, but a quite dangerous step in itself. PIO reading is functional
   again. The next step will be the unification of the write path of course.

 - Introduce a small helper for the execution of task file commands which
   basically just send a simple command down to the drive.

 - Add a buffer parameter to ide_raw_taskfile allowing to unify the handling of
   ioctl and normal ide_raw_taskfile request.

 - Fix some small function pointer type mismatches.

Apply more host chip controller clenups by Bartlomiej:

     - move setting drive->current_speed from *_tune_chipset()
       to ide_config_drive_speed()

    cmd64x.c:
	- convert cmd64x_tuneproc() to use ata-timing library
	- clean cmd64x_tune_chipset() and cmd680_tune_chipset()

    hpt366.c:
	- remove empty timings table

    it8172.c:
	- kill prototypes
	- update to new udma_setup() scheme

    - misc cleanups