ata_piix: subsys 106b:00a3 is apple ich8m too

Subsys 106b:00a3 also is the weird apple ich8m which chokes when the
latter two ports are accessed, add it.  Reported by Felipe Sere.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Felipe Sere <dodofxp@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>