ata_piix: Add Toshiba Satellite R20 and Tecra M6 to broken suspend list.

Add Toshiba Satellite R20 and Tecra M6 to broken suspend list.  Matt
Piermarini reported and provided the M6 patch.  This is from OSDL bug 7780.

Signed-off-by: Peter Schwenke <peter@bluetoad.com.au>
Cc: Matt Piermarini <mattpiermarini@yahoo.com>
Acked-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>