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

[Yu-Ping Wu (Code Review)]

Attention is currently required from: Hung-Te Lin, Jarried Lin, Xi Chen, Yidi Lin.

Yu-Ping Wu 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 MTK common directory
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Patch Set 1:

(3 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/83570/comment/1bbd77ea_f83857d4?usp... :
PS1, Line 7: MTK
MediaTek

https://review.coreboot.org/c/coreboot/+/83570/comment/4b6d4d21_7f075659?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.

https://review.coreboot.org/c/coreboot/+/83570/comment/2032b140_3c380112?usp... :
PS1, Line 13: rauru
There's no such thing (yet). For this patch the test should be something like "Build asurada".