[S] Change in flashrom[1.5.x]: doc: Add section about v1.5.1 into release notes

[Anastasia Klimchuk (Code Review)]

Attention is currently required from: Matt DeVillier, Peter Marheine.

Anastasia Klimchuk has posted comments on this change by Anastasia Klimchuk. ( https://review.coreboot.org/c/flashrom/+/85655?usp=email )

Change subject: doc: Add section about v1.5.1 into release notes
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Patch Set 2:

(1 comment)

Patchset:

PS2: 
Peter, thank you so much for review!
The wording I tried to make such that I don't need to return back and change after putting a tag (which we usually do with main releases).

I will later cherry-pick to main, so that it can be published on the website. But that will be after the tag.