am 18a0a4eb: (-s ours) am a3af3a74: (-s ours) hammerhead: update prebuilt kernel

* commit '18a0a4ebfa62b7624b5a3b08e837f174c1204c21':
tree: b74aa191ac219c45a56f93a9e56a4d76bd396e4f
  1. zImage-dtb