[XS] Change in coreboot[main]: libpayload: Make GPL commonlib includes available to payloads and tests

[Maximilian Brune (Code Review)]

Attention is currently required from: Jakub Czapiga, Julius Werner, Yu-Ping Wu.

Maximilian Brune has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/81287?usp=email )

Change subject: libpayload: Make GPL commonlib includes available to payloads and tests
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Patch Set 2: Code-Review+2

(1 comment)

Commit Message:

https://review.coreboot.org/c/coreboot/+/81287/comment/f13595c4_ef9425be :
PS2, Line 11: so that payloads can also call
            : the functions in them directly.
> I'm not sure I understand the question? This doesn't really have anything to do with `libpayload.h`. […]

I know it is unrelated, but it still confuses me why we have `libpayload.h` and thought maybe you could shine some light on it for me.