[L] Change in flashrom[master]: programmer: Add bitbanging programmer driver for Linux libgpiod

[Nico Huber (Code Review)]

Attention is currently required from: Thomas Heijligen, Angel Pons, Anastasia Klimchuk, Steve Markgraf.

Nico Huber has posted comments on this change. ( https://review.coreboot.org/c/flashrom/+/71801 )

Change subject: programmer: Add bitbanging programmer driver for Linux libgpiod
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Patch Set 7:

(2 comments)

Patchset:

PS6:
> Steve, just wanted to check, is everything alright? Not sure if you are busy, or maybe you have some […]

Renamed and added a `dev` option. Both `dev` and `gpiochip` are possible now.

PS6:
> Hello Steve! We have some comments on the patch, but it looks like maybe you don't have much time at […]

I talked to Steve on IRC a while ago. He was occupied with other things and agreed
that I'd take it over. I've backported the merged commit from flashrom-stable plus
one fixup for the renaming.