sh: mach-microdev: SuperIO-relative ioport mapping.

The microdev only has to contend with silly PIO mangling on anything
within the SuperIO range. As each of the SuperIO modules is already
speciail cased, we just shift that logic over to the ioport map.

With microdev PCI never being merged (and being fudamentally broken in
hardware), and the ethernet chip only doing 16-bit accesses already,
there's no need to maintain any of the extra special casing. Kill it all
off.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>