Move control plane static pod TLS assets to /etc/kubernetes/pki

* Change control plane static pods to mount `/etc/kubernetes/pki`,
instead of `/etc/kubernetes/bootstrap-secrets` to better reflect
their purpose and match some loose conventions upstream
* Place control plane and bootstrap TLS assets and kubeconfig's
in `/etc/kubernetes/pki`
* Mount to `/etc/kubernetes/pki` (rather than `/etc/kubernetes/secrets`)
to match the host location (less surprise)

Rel: https://github.com/poseidon/terraform-render-bootstrap/pull/233

google-cloud/flatcar-linux/kubernetes/cl/controller.yaml

@@ -117,7 +117,7 @@ systemd:
         WorkingDirectory=/opt/bootstrap
         Environment=KUBELET_IMAGE=quay.io/poseidon/kubelet:v1.19.4
         ExecStart=/usr/bin/docker run \
-            -v /etc/kubernetes/bootstrap-secrets:/etc/kubernetes/secrets:ro \
+            -v /etc/kubernetes/pki:/etc/kubernetes/pki:ro \
             -v /opt/bootstrap/assets:/assets:ro \
             -v /opt/bootstrap/apply:/apply:ro \
             --entrypoint=/apply \
@@ -147,14 +147,14 @@ storage:
           mkdir -p -- auth tls/etcd tls/k8s static-manifests manifests/coredns manifests-networking
           awk '/#####/ {filename=$2; next} {print > filename}' assets
           mkdir -p /etc/ssl/etcd/etcd
-          mkdir -p /etc/kubernetes/bootstrap-secrets
+          mkdir -p /etc/kubernetes/pki
           mv tls/etcd/{peer*,server*} /etc/ssl/etcd/etcd/
-          mv tls/etcd/etcd-client* /etc/kubernetes/bootstrap-secrets/
+          mv tls/etcd/etcd-client* /etc/kubernetes/pki/
           chown -R etcd:etcd /etc/ssl/etcd
           chmod -R 500 /etc/ssl/etcd
           chmod -R 700 /var/lib/etcd
-          mv auth/* /etc/kubernetes/bootstrap-secrets/
-          mv tls/k8s/* /etc/kubernetes/bootstrap-secrets/
+          mv auth/* /etc/kubernetes/pki/
+          mv tls/k8s/* /etc/kubernetes/pki/
           mkdir -p /etc/kubernetes/manifests
           mv static-manifests/* /etc/kubernetes/manifests/
           mkdir -p /opt/bootstrap/assets
@@ -167,7 +167,7 @@ storage:
       contents:
         inline: |
           #!/bin/bash -e
-          export KUBECONFIG=/etc/kubernetes/secrets/admin.conf
+          export KUBECONFIG=/etc/kubernetes/pki/admin.conf
           until kubectl version; do
             echo "Waiting for static pod control plane"
             sleep 5