[M] Change in coreboot[master]: util/sconfig: Include optional maiboard chip header

[Karthik Ramasubramanian (Code Review)]

Attention is currently required from: Raul Rangel, Martin L Roth, Jon Murphy, Arthur Heymans, Tim Van Patten, Angel Pons, Felix Held.

Karthik Ramasubramanian has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/74736 )

Change subject: util/sconfig: Include optional maiboard chip header
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Patch Set 4:

(1 comment)

File util/sconfig/main.c:

https://review.coreboot.org/c/coreboot/+/74736/comment/218209e9_accfcc2e 
PS3, Line 1402: &chip_h[strlen("src/")]
> > Mainboard path is got from devicetree path which in turn always contains "src/" […]

Done. Added code to handle that condition so that it is clear where to look for when things don't meet the expectation.