[coreboot] The attachment of AMD RS690 chipset

[Xie, Michael]

Hi,
Attachment is the patch for AMD RS690 chipset. It is signed off by Michael Xie and reviewed by Marc Jones. All the PCIe slots are enabled in this patch except power management.

<<rs690.patch>> 
Signed-off-by:  Michael Xie [e-mail]
Reviewed-by: Marc Jones