canal should mount xtables.lock to share the lock with other processes like kube-proxy

roles/network_plugin/canal/templates/canal-node.yaml.j2

@@ -51,6 +51,10 @@ spec:
         - name: "canal-certs"
           hostPath:
             path: "{{ canal_cert_dir }}"
+        - name: xtables-lock
+          hostPath:
+            path: /run/xtables.lock
+            type: FileOrCreate
       containers:
         # Runs the flannel daemon to enable vxlan networking between
         # container hosts.
@@ -128,6 +132,9 @@ spec:
             - name: "canal-certs"
               mountPath: "{{ canal_cert_dir }}"
               readOnly: true
+            - name: xtables-lock
+              mountPath: /run/xtables.lock
+              readOnly: false
         # Runs calico/node container on each Kubernetes node.  This
         # container programs network policy and local routes on each
         # host.