[L] Change in flashrom[main]: doc: Convert write-protect docs to sphinx

[Anastasia Klimchuk (Code Review)]

Attention is currently required from: Sergii Dmytruk, Thomas Heijligen.

Anastasia Klimchuk has posted comments on this change. ( https://review.coreboot.org/c/flashrom/+/78113?usp=email )

Change subject: doc: Convert write-protect docs to sphinx
......................................................................

Patch Set 2:

(3 comments)

File doc/user_docs/example_partial_wp.rst:

https://review.coreboot.org/c/flashrom/+/78113/comment/987e0838_af9d1098 :
PS1, Line 102: control
> `(sector/block-based)` can be added after `control` because I had to pause for a moment to recall wh […]

Done

https://review.coreboot.org/c/flashrom/+/78113/comment/ba907179_c1dcf521 :
PS1, Line 103: 4 November 2022
> Block-based write-protection isn't supported as of today, so the date can be updated accordingly.

Done

File doc/user_docs/fw_updates_vs_spi_wp.rst:

https://review.coreboot.org/c/flashrom/+/78113/comment/93c1d6f9_69860ad7 :
PS1, Line 62: 4 November 2022)
> CB:69517 changed the behaviour to use WP code and and then old implementation as a fallback. […]

I removed the paragraph. The change CB:69517 is not a part of v1.3.
But I am hoping to get some help from other people and a piece of good luck and be able to do another release this year :)