libata: Change prototype of mode_filter to remove ata_port*

With Tejun having added adev->ap some time ago we can get rid of the
almost unused port being passed to mode filters. And while we are
doing filters, lets turn on the !IORDY filter as well.

Signed-off-by: Alan Cox <alan@redhat.com>

With some hand massaging from
Signed-off-by: Jeff Garzik <jeff@garzik.org>