[M] Change in flashrom[master]: layout: Factor out flash_region structure from romentry

[Anastasia Klimchuk (Code Review)]

Attention is currently required from: Edward O'Callaghan, Angel Pons, Nikolai Artemiev.

Anastasia Klimchuk has posted comments on this change. ( https://review.coreboot.org/c/flashrom/+/69196 )

Change subject: layout: Factor out flash_region structure from romentry
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Patch Set 6: Code-Review+1

(2 comments)

Commit Message:

https://review.coreboot.org/c/flashrom/+/69196/comment/07b32588_217f7588 
PS6, Line 16: TEST=builds
Have you done any testing with layouts that have multiple regions?

Patchset:

PS2:
> That's a good question since this patch on its own doesn't have any extra context. […]

I agree commit message needs more info on why the patch exist, one more paragraph would be great, something around "The patch allows for ABC to be done / XYZ to be improved / OPQ to be fixed later in the chain".
As a reminder for Nikolai, b:260440773 is just a magic number, doesn't give any info.
Thanks!