[PATCH] libata: PIO 0

Ensure the pio_mode is always setup. Don't do any setup on the controller b
just ensure the mode reporting is valid to avoid tons of special cases
in PATA driver code when mode switching on the fly.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>