Change in coreboot[master]: mb/google/brya/var/agah: Add GPU power sequencing

[Tim Wawrzynczak (Code Review)]

Attention is currently required from: Ivy Jian, Angel Pons, Nick Vaccaro.
Tim Wawrzynczak has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/62384 )

Change subject: mb/google/brya/var/agah: Add GPU power sequencing
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Patch Set 7:

(2 comments)

File src/mainboard/google/brya/variants/agah/variant.c:

https://review.coreboot.org/c/coreboot/+/62384/comment/9c764039_3bb5c347 
PS6, Line 47:
> Why is this a tab?

oops

https://review.coreboot.org/c/coreboot/+/62384/comment/e5374d34_9034ac17 
PS6, Line 119: 	gpu_powered_on = dgpu_power_sequence_on() == CB_SUCCESS;
> `dgpu_power_sequence_on()` already sets `gpu_powered_on`

d'oh! fixed