VOL-5244 - branch and release voltha-protos.

.gitreview
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  o repo:voltha-protos is of the tag-then-branch-from-tag release flavor.
  o 25589d8 (HEAD -> voltha-2.12, tag: v2.12.0, origin/voltha-2.12)
  o Update release .gitreview default branch to voltha-2.12

Change-Id: I29d607b8187465ffe26e88af9f76c48b4e241fc2
2 files changed