code: func UseHostResolv(mnt fs.MountUnmounter, podRoot string) error {
  	return BindMount(
  		mnt,
  		"/etc/resolv.conf",
  		filepath.Join(_common.Stage1RootfsPath(podRoot), "etc/rkt-resolv.conf"),
  		true)
  }
docs: /*
   Bind-mount the hosts /etc/resolv.conf in to the stage1's /etc/rkt-resolv.conf.
   That file will then be bind-mounted in to the stage2 by perpare-app.c
  */