[coreboot-gerrit] Change in coreboot[master]: Add mediatek mt8192 dram vendor code

[Hung-Te Lin (Code Review)]

Attention is currently required from: Xi Chen, Martin Roth, Yu-Ping Wu.
Hung-Te Lin has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/50294 )

Change subject: Add mediatek mt8192 dram vendor code
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Patch Set 3:

(1 comment)

Patchset:

PS3: 
Hi xi, thanks for the change.

To make it easier, can you split the change to

1. vendor: Add Mediatek DRAM calibration reference code

2. soc/mediatek/mt8192: Initialize DRAM by MTK vendor implementation

3. soc/mediatek/mt8192: Remove unused DRAM init code

You can even merge 2/3 if that helps. But for adding new stuff into vendor code, I think it should be a standalone change, not removing/deleting code from soc folder.