Merge "Revert "hammerhead: update prebuilt kernel"" into mnc-dev am: f617d316ba  -s ours am: 8dddcd3b7e am: 08d7bac4b2
am: b4ddf3c19a

* commit 'b4ddf3c19a378da85936741c62cc08d685b3036f':
  Revert "hammerhead: update prebuilt kernel"