[PATCH] wd33c93 updates

The PC98 folks have some updates in their tree to make the generic
wd33c93 driver usable in PIO mode, but unfortunately the way they do it
(include a header specific to their lowlevel driver in wd33c93.c
conditionally) is rather ugly.

I reworked it to provide different implementations of the access method
inside wd33c93.c independent of the lowlevel driver.  In addition the
patch contains various patches to actually get the driver compile in 2.5
and a reindent to follow kernel codingstyle (sorry, but the maintainer
hasn't touched it for four years and it made my eyes bleed..)