[S] Change in coreboot[master]: mb/prodrive/hermes: Add libgfxinit support

[Angel Pons (Code Review)]

Attention is currently required from: Arthur Heymans, Patrick Rudolph, Christian Walter.

Angel Pons has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/62648 )

Change subject: mb/prodrive/hermes: Add libgfxinit support
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Patch Set 4:

(2 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/62648/comment/59717b30_8d912996 
PS4, Line 9: Tested DP port works. HDMI seems broken, but that is also the case in Linux.
> LSPCon is actually the only difference between the default and avalanche […]

I had a look at the actual hardware today. The Poseidon (default VBT) piggyback board has two DisplayPort connectors and an HDMI connector with the MegaChips LSPCON.

There's also a more sophisticated piggyback board, which includes SFP connectors. IIRC it has DVI-I with some chip, HDMI (I didn't see a LSPCON) and DisplayPort.

Patchset:

PS4: 
Will try to test this tomorrow.