Mount /etc/machine-id from host into Kubelet

* Kubelet node's System UUID can be detected from the sysfs
filesystem without a host mount, but if you need to distinguish
between the host's machine-id and SystemUUID
* On cloud platforms, MachineID and SystemUUID are identical,
but on bare-metal the two differ

aws/fedora-coreos/kubernetes/fcc/controller.yaml

@@ -71,6 +71,7 @@ systemd:
           --network host \
           --volume /etc/cni/net.d:/etc/cni/net.d:ro,z \
           --volume /etc/kubernetes:/etc/kubernetes:ro,z \
+          --volume /etc/machine-id:/etc/machine-id:ro \
           --volume /usr/lib/os-release:/etc/os-release:ro \
           --volume /lib/modules:/lib/modules:ro \
           --volume /run:/run \

aws/fedora-coreos/kubernetes/workers/fcc/worker.yaml

@@ -44,6 +44,7 @@ systemd:
           --network host \
           --volume /etc/cni/net.d:/etc/cni/net.d:ro,z \
           --volume /etc/kubernetes:/etc/kubernetes:ro,z \
+          --volume /etc/machine-id:/etc/machine-id:ro \
           --volume /usr/lib/os-release:/etc/os-release:ro \
           --volume /lib/modules:/lib/modules:ro \
           --volume /run:/run \