[coreboot] Unifying AMD SB700/SB800/SB900 code base

[ron minnich]

Unless you're prepared to test and verify on the exact hardware, don't
do it. We've had lots of well-intentioned efforts like this over the
years that broke platforms. I don't like finding that somebody has
broken a platform 2 years after a cosmetic improvement of this sort
was made. And that has happened.

Don't do it. This type of merging is almost always a mistake.

Kernel code does not do nearly as much complex work as firmware code.
Kernels have it easy. That lesson has been learned many times. The
kernel is not a guide for firmware work.

ron