Change in coreboot[master]: mb/google/dedede/var/magolor: Set core display clock to 172.8 MHz

[Nico Huber (Code Review)]

Attention is currently required from: Henry Sun, Ren Kuo, Paul Menzel, Simon Yang, Angel Pons, Kane Chen, Karthik Ramasubramanian.
Nico Huber has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/60301 )

Change subject: mb/google/dedede/var/magolor: Set core display clock to 172.8 MHz
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Patch Set 10: Code-Review+2

(1 comment)

Commit Message:

https://review.coreboot.org/c/coreboot/+/60301/comment/417f4202_95560d89 
PS9, Line 12: per Intel recommendation
> If Ren choice to change it by function mainboard_silicon_init_params() in ramstage.c, maybe I can drop my change first, and once FSP updated, I can go back here to update related header file, what do you think?

It's already written, so let's just get it in. :)

It would be nice to mention as much as possible about the FSP issue in the
commit message. So if somebody else runs into this problem, they'd know
what to do.