Change in coreboot[master]: lib/cbfs.c: Fix return value of failure to measure

[Arthur Heymans (Code Review)]

Attention is currently required from: Jonathan Zhang, Johnny Lin, Julius Werner, Deomid "rojer" Ryabkov.
Arthur Heymans has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/51099 )

Change subject: lib/cbfs.c: Fix return value of failure to measure
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Patch Set 1:

(1 comment)

Commit Message:

https://review.coreboot.org/c/coreboot/+/51099/comment/d70a4f97_71830073 
PS1, Line 10: bootable.
> Makes sense. On the other hand, when S-ACM figured out the image is not signed correctly, should coreboot not attempt to measure?

It's the ACM LockConfig call that probably messes up the TPM if the image was not properly set up. It's probably a good idea to skip it if we know it will fail and cause other issues. That way measured boot can work even if CBnT has issues of was inproperly configured.