[S] Change in coreboot[main]: util/lint: Add lint rule to warn if <stddef.h> is included but not used

[Elyes Haouas (Code Review)]

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

Elyes Haouas has posted comments on this change by Elyes Haouas. ( https://review.coreboot.org/c/coreboot/+/82670?usp=email )

Change subject: util/lint: Add lint rule to warn if <stddef.h> is included but not used
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Patch Set 5:

(1 comment)

Patchset:

PS5: 
Additionally, I have created a combined script that checks <string.h>, <stdint.h>, and <stddef.h> in a single file for your review: https://review.coreboot.org/c/coreboot/+/82713

Please review the scripts and provide your feedback. We need to decide whether to opt for the individual scripts for each header or to use the combined script that handles all three headers together.