[M] Change in coreboot[main]: util/lint: Add lint rule to avoid duplicated includes

[Elyes Haouas (Code Review)]

Attention is currently required from: Arthur Heymans, Julius Werner, Martin L Roth, Nico Huber.

Elyes Haouas has posted comments on this change by Elyes Haouas. ( https://review.coreboot.org/c/coreboot/+/81907?usp=email )

Change subject: util/lint: Add lint rule to avoid duplicated includes
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Patch Set 5:

(1 comment)

File util/lint/lint-stable-031-includes:

https://review.coreboot.org/c/coreboot/+/81907/comment/7ee54566_f0e838d1?usp... :
PS5, Line 56: check_duplicates '<arch/pci_ops.h>' '<device/pci_ops.h>'
> I guess if we want to enforce things, we'd first have to decide on the rules? […]

about <string.h>, I found it here https://review.coreboot.org/c/coreboot/+/39468

You are right, we need a rules for that.

The patch I've sent is based on 'IWYU pragma: export' comments in coreboot tree.