Change in coreboot[master]: soc/mediatek/mt8186: Add DRAM full calibration support

[Paul Menzel (Code Review)]

Attention is currently required from: Hung-Te Lin, Rex-BC Chen, Ryan Chuang.
Paul Menzel has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/60318 )

Change subject: soc/mediatek/mt8186: Add DRAM full calibration support
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Patch Set 7:

(2 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/60318/comment/8a7c4349_58feb0d3 
PS7, Line 10: We remove emi.h because emi.h is defined in common/include/soc.
Please make that a separate commit.

Patchset:

PS7: 
Please also split SOC and mainboard changes into separate commits.