[S] Change in flashrom[main]: Correct get_flash_region() to use inclusive upper bounds

[Peter Marheine (Code Review)]

Attention is currently required from: Aarya, Nikolai Artemiev.

Peter Marheine has posted comments on this change by Peter Marheine. ( https://review.coreboot.org/c/flashrom/+/82496?usp=email )

Change subject: Correct get_flash_region() to use inclusive upper bounds
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Patch Set 7:

(1 comment)

Patchset:

PS6:
> I tested reading flash on a yaviks board both with and without this patch, and it looks okay. […]

I happened to be doing some other firmware work on the same machine I tested reading on and discovered a `region.end - 1` in erase code that only exists in ChromeOS which breaks erase, but after patching that the whole read/erase/write process worked fine.