Change in flashrom[master]: libflashrom,writeprotect: add flashrom_wp_{get,set}_mode()

[Nikolai Artemiev (Code Review)]

Attention is currently required from: Nico Huber, Edward O'Callaghan, Angel Pons, Anastasia Klimchuk, Sergii Dmytruk.
Nikolai Artemiev has posted comments on this change. ( https://review.coreboot.org/c/flashrom/+/58483 )

Change subject: libflashrom,writeprotect: add flashrom_wp_{get,set}_mode()
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Patch Set 10:

(1 comment)

File cli_classic.c:

https://review.coreboot.org/c/flashrom/+/58483/comment/39133b8f_31d79a77 
PS7, Line 64: --wp-enable
> `--wp-enable` takes an optional argument, which isn't mentioned here.

Done. Since this CL isn't changing cli_classic anymore I decided to do it here: https://review.coreboot.org/c/flashrom/+/58738/3.

Also, we might actually want to remove the mode argument, trying to activate anything other than hardware WP will usually fail.