[M] Change in coreboot[master]: soc/amd/common/block/spi: Mainboard to override SPI Read Mode

[Jon Murphy (Code Review)]

Attention is currently required from: Jason Glenesk, Raul Rangel, Jason Nien, Matt DeVillier, Martin Roth, Fred Reitberger, Karthik Ramasubramanian, Felix Held.

Jon Murphy has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/68946 )

Change subject: soc/amd/common/block/spi: Mainboard to override SPI Read Mode
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Patch Set 1:

(2 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/68946/comment/74c6810b_38a575b7 
PS1, Line 15: BUG=b:225213679
This bug was marked dupe, and the one that it's a dupe of was marked won't fix infeasible, is this really the right bug?

File src/mainboard/google/guybrush/spi_speeds.c:

https://review.coreboot.org/c/coreboot/+/68946/comment/03b02890_8dc48def 
PS1, Line 7: void mainboard_spi_cfg_override(uint8_t *fast_speed, uint8_t *read_mode)
Rename variable speed?  It's no longer solely the fast speed