Change in coreboot[master]: Documentation: Codify some guidelines for headers and chain-including

[HAOUAS Elyes (Code Review)]

Attention is currently required from: Martin Roth, Julius Werner.
HAOUAS Elyes has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/50247 )

Change subject: Documentation: Codify some guidelines for headers and chain-including
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Patch Set 1:

(1 comment)

Patchset:

PS1:
> I'd rather have Elyes ask before pushing 20 changes on the topic for review too. […]

Please see https://review.coreboot.org/c/coreboot/+/50286 
Thx