Basically PCI driver handling reorganization. This is one step further
ahead toward the goal of fully modularized host chip drivers.

 - Adjust ide-scsi to the new error handling. Just don't try any device
   resets there.

 - Add unmasking of IRQ per default to the PMac PCI code.

 - Split up the crap table from ide-pci. Let the corresponding drivers do
   registration of the functions they provide. This small change makes
   this patch rather big.

 - Hard-code the number of ports requested for DMA engines. They are always
   precisely 8 on PCs. If you hove something different to deal with,
   well then please just provide your own init_dma method.

 - Remove the HDIO_GETGEO_BIG ioctl. Patch by Andries Brouwer. Applies
   unmodified.

 - Make ON_BOARD be equal 0, so we can spare ourself some typing in structure
   initialization.

 - Normalize the terminology in the host chip drivers. It will make spotting
   the tons of common code found there later easier.