[M] Change in flashrom[master]: ichspi.c: Read chip ID and use it to identify chip

[Edward O'Callaghan (Code Review)]

Attention is currently required from: Angel Pons, Nikolai Artemiev.

Edward O'Callaghan has posted comments on this change. ( https://review.coreboot.org/c/flashrom/+/69195 )

Change subject: ichspi.c: Read chip ID and use it to identify chip
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Patch Set 2:

(2 comments)

Commit Message:

https://review.coreboot.org/c/flashrom/+/69195/comment/4ecaa7c5_8372e272 
PS2, Line 9: BUG=b:253715389,b:253713774
> Out of curiosity, what are these bug tracker entries about?

Yep, please include the details here Nik so the story is more complete for upstream but also the git history.

Specifically explain how CSME presents a quasi-opaque chip however you still need to understand the chip behind hwseq for things like wp.
```
    	/* support writeprotect. */
    	flash->chip->reg_bits = entry->reg_bits;
    	flash->chip->decode_range = entry->decode_range;
```

https://review.coreboot.org/c/flashrom/+/69195/comment/4a46fa58_e39be76e 
PS2, Line 11: TEST=builds
I think you can include this was actually tested here across the DUT pool?