[M] Change in coreboot[main]: soc/mediatek: Move symbols.h into MediaTek common directory

[Jarried Lin (Code Review)]

Attention is currently required from: Hung-Te Lin, Xi Chen, Yidi Lin, Yu-Ping Wu.

Jarried Lin has posted comments on this change by Jarried Lin. ( https://review.coreboot.org/c/coreboot/+/83570?usp=email )

Change subject: soc/mediatek: Move symbols.h into MediaTek common directory
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Patch Set 2:

(3 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/83570/comment/28168a72_24dac058?usp... :
PS1, Line 7: MTK
> MediaTek

Done

https://review.coreboot.org/c/coreboot/+/83570/comment/bdd8be35_e3aacd1d?usp... :
PS1, Line 9: Because the declaration of MTK SOCs are gernerally the same.
           : Share a common soc/symbols.h.
> To reduce duplicate region declarations of MediaTek SoCs, move the header file to a common directory […]

Done

https://review.coreboot.org/c/coreboot/+/83570/comment/d2dd7278_f3c1f220?usp... :
PS1, Line 13: rauru
> There's no such thing (yet). For this patch the test should be something like "Build asurada".

Done