Change in flashrom[master]: ichspi.c: Implement read_write_status for wp

[Edward O'Callaghan (Code Review)]

Attention is currently required from: Nikolai Artemiev, Sergii Dmytruk.
Edward O'Callaghan has posted comments on this change. ( https://review.coreboot.org/c/flashrom/+/64540 )

Change subject: ichspi.c: Implement read_write_status for wp
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Patch Set 3:

(2 comments)

File ichspi.c:

https://review.coreboot.org/c/flashrom/+/64540/comment/6d73b75d_b460fe51 
PS2, Line 1349: static int ich_hwseq_read_status(const struct flashctx *flash, enum flash_reg reg_, uint8_t *value)
> I think both functions should fail if reg_ is not SR1.

Done

https://review.coreboot.org/c/flashrom/+/64540/comment/5d99b916_e7b1bcf5 
PS2, Line 1352:         int len = 1;
> I'd make len a constant in both functions. […]

Done