Change in coreboot[master]: mb/google/skyrim/var/skyrim: Add audio codec and amp support

[reddysujith (Code Review)]

Attention is currently required from: V sujith kumar Reddy, Raul Rangel, Ian Feng, Chris Wang, Karthik Ramasubramanian.
reddysujith has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/63779 )

Change subject: mb/google/skyrim/var/skyrim: Add audio codec and amp support
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Patch Set 4:

(1 comment)

File src/mainboard/google/skyrim/variants/skyrim/overridetree.cb:

https://review.coreboot.org/c/coreboot/+/63779/comment/c82cfc38_5a3d5705 
PS4, Line 174: ACPI_GPIO_IRQ_LEVEL_LOW
> I use fw_config to differentiate the two audio codec setting. […]

This is codec requirement on states( LEVEL_LOW and EDGE_BOTH).
we can check this in the below links

https://elixir.bootlin.com/linux/latest/source/sound/soc/codecs/rt5682s.c#L3...
https://elixir.bootlin.com/linux/latest/source/sound/soc/codecs/nau8825.c#L2...