The UDMA66 VIA hardware has no controller side cable detect bits we can
use. This patch minimally fixes the problem by reporting unknown in this
case and using drive side detection.

The old drivers/ide code does some additional tricks but those aren't
appropriate now we are in -rc.

Without this update UDMA66 via controllers run slowly. They don't fail so
it's a borderline call whether this is -rc material or not.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>