Change in coreboot[master]: mb/google/volteer/variant/lindar: Enable SA GV setting

[Tim Wawrzynczak (Code Review)]

Attention is currently required from: Kevin Chang, Caveh Jalali, Paul Menzel, Derek Huang, Zhuohao Lee.
Tim Wawrzynczak has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/49636 )

Change subject: mb/google/volteer/variant/lindar: Enable SA GV setting
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Patch Set 4: Code-Review+2

(1 comment)

Commit Message:

https://review.coreboot.org/c/coreboot/+/49636/comment/b002bb4a_a68b9300 
PS1, Line 9: Allow MRC training in SaGv.
> Done

SaGv is System Agent Geyserville; it's functionality that allows the System Agent to lower the frequency/voltage operating point for DRAM accesses when the system is in some idle states.