Ensure all required kubelet mount points exists

[andrewrynhard]

It might be good to double check how we run the kubelet in Talos against this: kubernetes/kubernetes#74148 (comment)

[bradbeam]

Comparing against the list there's a few deltas with regards to what is being shared with the container --

• instances of additional binaries and libraries being mounted up ( mkfs.xfs / iscsiadm )
• host ssl certs
• cni config + binaries

I could see a case for sharing host ssl certs with hyperkube, but the additional binaries seem redundant ( hyperkube already contains mkfs.xfs/ext{2,3,4} ) along with the most recent cni release at the time the hyperkube version was released ( so perhaps we can trim that out of our rootfs ( https://github.com/autonomy/talos/blob/master/Dockerfile#L171-L174 ).