As the final step, add the `dockerless` tags to all files in the
dockershim. Using `-tags=dockerless` in `go build`, we can compile
kubelet without the dockershim.
Once cadvisor no longer depends on `docker/docker`, compiling with
`-tags=dockerless` should be sufficient to compile the Kubelet w/o a
dependency on `docker/docker`.
To ensure kubelet doesn't attempt network teardown on HostNetwork
containers that no longer exist but are still checkpointed, make
sure we preserve the HostNetwork property in checkpoints. If
the checkpoint indicates the container was a HostNetwork one,
don't tear down the network since that would fail anyway.
Related: https://github.com/kubernetes/kubernetes/issues/44307#issuecomment-299548609
