Change in coreboot[master]: soc/mediatek/mt8186: Add a stub implementation of the MT8186 SoC

[Rex-BC Chen (Code Review)]

Attention is currently required from: Paul Menzel, Felix Held.
Rex-BC Chen has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/58640 )

Change subject: soc/mediatek/mt8186: Add a stub implementation of the MT8186 SoC
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Patch Set 2:

(1 comment)

File src/soc/mediatek/mt8186/include/soc/timer.h:

PS2:
> This is the same as `mt8195/include/soc/timer.h` for example.

There may be some designs which are the same for MediaTek SoCs, and this patch is just a basic setting for MT8186.
There are more settings for other modules.
In timer's case, 8195 and 8186 are using the same design which using v2 for timer.