[S] Change in flashrom[master]: spi25_statusreg: support reading/writing configuration register

[Sergii Dmytruk (Code Review)]

Attention is currently required from: Nico Huber, Edward O'Callaghan, Angel Pons, Anastasia Klimchuk.

Sergii Dmytruk has posted comments on this change. ( https://review.coreboot.org/c/flashrom/+/66211 )

Change subject: spi25_statusreg: support reading/writing configuration register
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Patch Set 8:

(1 comment)

Patchset:

PS2: 
Rebased everything due to `flashchips.c` changes and moved aliasing to CB:69399 restoring an older patchset here.
> it seemed to make the code simpler

I guess it depends on how you look at it.  Aliasing does make SPI code changes smaller and keeps fewer entities to know about, but I think Edward's argument is that not using aliasing makes understanding and modifying code easier, because it has more obvious structure.