[coreboot-gerrit] Change in coreboot[master]: mb/google/volteer: Create drobit variant

[Ken Lu (Code Review)]

Ken Lu has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/47358 )

Change subject: mb/google/volteer: Create drobit variant
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Patch Set 2:

This CL is create for issue root cause investigation .