[S] Change in coreboot[master]: mb/google/guybrush: enable display backlight in ramstage

[Matt DeVillier (Code Review)]

Attention is currently required from: Raul Rangel, Jason Nien, Rob Barnes, Karthik Ramasubramanian.

Matt DeVillier has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/67246 )

Change subject: mb/google/guybrush: enable display backlight in ramstage
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Patch Set 1:

(1 comment)

File src/mainboard/google/guybrush/variants/baseboard/gpio.c:

https://review.coreboot.org/c/coreboot/+/67246/comment/18cf170d_2807f80f 
PS1, Line 141: PAD_GPO
> The pin seems to be in the S5 domain, so it should retain its value

looking at the original bug, it seemed that some SKUs were having issues with the backlight being restored at min value coming out of Si0x, and using ACPI to set the backlight was part of the workaround. I'm unable to reproduce that problem on Dewatt though.