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

[Angel Pons (Code Review)]

Attention is currently required from: Julius Werner.
Angel Pons 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 2:

(1 comment)

File Documentation/coding_style.md:

https://review.coreboot.org/c/coreboot/+/50247/comment/355b9a86_b9326722 
PS2, Line 840: Headers should always be included at the top of the file
I personally believe that, for specific files, it makes more sense to not include everything at the top. IMHO, src/northbridge/intel/haswell/haswell.h is an example of such a thing: includes are ordered along with other definitions by topic.