[L] Change in coreboot[master]: Migrate https://www.coreboot.org/EHCI_Debug_Port to docs

[David Hubbard (Code Review)]

David Hubbard has uploaded a new patch set (#3). ( https://review.coreboot.org/c/coreboot/+/72956 )

Change subject: Migrate https://www.coreboot.org/EHCI_Debug_Port to docs
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Migrate https://www.coreboot.org/EHCI_Debug_Port to docs

The coreboot documentation about the EHCI Debug Port appears to be the
most comprehensive resource on the net on the topic. Updated to at least
mention the XHCI Debug cable as well, without committing to coreboot
support.

This also cleans up the organization a bit and adds two new links
in the "External Resources" section.

This drops the wiki's pictures it had of the Ajays NET20DC or AMIDebug Rx
because they have disappeared even from the secondhand market and mostly
are obsolete now.

Change-Id: Ifaef2a6bd770a8888015bedb1c818b53e1c4391f
Signed-off-by: David Hubbard 
---
M Documentation/external_docs.md
A Documentation/lib/usb_debug_port.md
2 files changed, 262 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/56/72956/3