[L] Change in coreboot[main]: [RFC] Add UPL FDT handoff

[Maximilian Brune (Code Review)]

Attention is currently required from: Arthur Heymans, Jakub Czapiga, Julius Werner, Jérémy Compostella, Lean Sheng Tan, Matt DeVillier, Philipp Hug, Simon Glass, ron minnich.

Maximilian Brune has posted comments on this change by Maximilian Brune. ( https://review.coreboot.org/c/coreboot/+/76591?usp=email )

Change subject: [RFC] Add UPL FDT handoff
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Patch Set 21:

(1 comment)

File payloads/libpayload/arch/arm/coreboot.c:

https://review.coreboot.org/c/coreboot/+/76591/comment/51687e6c_5b618cc5?usp... :
PS17, Line 60: if (CONFIG(LP_UPL))
> Done

Jenkins just made me realize that we cannot do that in runtime, because UPL is GPL licensed code (through `commonlib/device_tree`) and if I always built in both coreboot table and UPL parser we wouldn't be able to create payloads anymore that are fully BSD.