Explicitly create cni bin dir

If this path doesnt exist, it will cause kubelet to fail to start when
using rkt

roles/kubernetes/node/tasks/main.yml

@@ -7,6 +7,12 @@
 - include: pre_upgrade.yml
   tags: kubelet
 
+- name: Ensure /var/lib/cni exists
+  file:
+    path: /var/lib/cni
+    state: directory
+    mode: 0755
+
 - include: install.yml
   tags: kubelet