[PATCH EHCI Debug Port setup for all AMD SB600/SB700 boards

[Uwe Hermann]

See patch.

I also cleaned up the Debug Port page in the wiki a bit.

http://www.coreboot.org/EHCI_Debug_Port

For now I marked all chipsets where we have Debug Port code as untested,
I have a feeling the functionality was rarely tested recently (or at
all) so we should only mark those chipsets as tested where we actually
have recent test reports.

I'm not sure about the SiS966 Debug Port code, it looks copy-pasted from
MCP55 to me, not sure if the functionality actually exists on that
chipset and if the code is correct for that. Maybe someone with a SiS966
board could test this?

I'll be able to test on two more chipsets (MCP55, ICH7) and mark them
as tested in the wiki then, will report back. Can somebody test SB700?
I guess it works fine as the SB600 does too, but a test report would be
nice.

Uwe.