[XS] Change in coreboot[main]: soc/mediatek/common: Reduce eMMC clock frequency to 400 kHz

[Kiwi Liu (Code Review)]

Attention is currently required from: Kiwi Liu, Mengqi Zhang, Paul Menzel.

Kiwi Liu has posted comments on this change by Kiwi Liu. ( https://review.coreboot.org/c/coreboot/+/84298?usp=email )

Change subject: soc/mediatek/common: Reduce eMMC clock frequency to 400 kHz
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Patch Set 10:

(1 comment)

Commit Message:

https://review.coreboot.org/c/coreboot/+/84298/comment/cba0cdc6_f594e155?usp... :
PS9, Line 13: measure eMMC clock ok
            :
> Did you measure with an oscilloscope? What did it show exactly?

https://partnerissuetracker.corp.google.com/issues/356578805#comment26
YES, measure with an oscilloscope.