- Eliminate the mate member of the ata_channel structure. The information
   provided by it is already present. This patch may have undesirable
   effects on the ns87415.c and trm290.c host chip drivers, but it's worth
   for structural reasons to have it.

- Kill unused code, which was "fixing" interrupt routing from ide-pci.c Don't
   pass any "mate" between the functions there.

- Don't define SUPPORT_VLB_SYNC unconditionally in ide-taskfile.c

- Apply Vojtech Pavliks fix for piix host-chip driver crashes.

- Add linux/types.h to ide-pnp.c.

- Apply latest sis5513 host chip driver patch from by Lionel Bouton by hand.

- Apply patch by Paul Macerras for power-mac.

- Try to make the ns87415 driver a bit more reentrant.