Change in flashrom[master]: spi25_statusreg.c: Allow opaque masters to hook spi_{rw}_register()

[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/+/64375 )

Change subject: spi25_statusreg.c: Allow opaque masters to hook spi_{rw}_register()
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Patch Set 5: Code-Review-1

(1 comment)

File spi25_statusreg.c:

https://review.coreboot.org/c/flashrom/+/64375/comment/e19c8ce1_3afee909 
PS5, Line 33: 	if ((flash->mst->buses_supported & BUS_PROG) && flash->mst->opaque.write_register) {
            : 		return flash->mst->opaque.write_register(flash, reg, value);
            : 	}
I am inclined to move this specalisation to actually within writeprotect.c I feel this layer violates as-is and that flashrom probably should be refactored some to wrap up the spi command issuing semantics and master selection behind some kind of internal API.