pata_hpt3x3: major reworking and testing

The HPT343/345 (aka 363) is a bit of a warped device.  For many setups you
need to access the other registers via BAR4 offsets.  PIO is now rock
solid, DMA isn't.  Unfortunately the drivers/ide hpt34x driver is
completely broken so doesn't help further debug.

Signed-off-by: Alan Cox <alan@redhat.com>
Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>