am ad21a1f6: (-s ours) Merge "Revert "DO NOT MERGE: Add generic IP packet code and use it for GRE."" into klp-dev

* commit 'ad21a1f63cbc6a0ef5d207c4bab38171bfcecd76':
  Revert "DO NOT MERGE: Add generic IP packet code and use it for GRE."