fix volume mount error in stackube-proxy

As kubernetes support mount propogation now, the "shared" propogation
type is not needed any more and would cause volume mount error.

Change-Id: Idfa718ff7f0591ed246dc06f4a78c886abe9efe2
Signed-off-by: Li Wei <liwei@anbutu.com>

deployment/stackube-proxy.yaml

@@ -109,9 +109,7 @@ spec:
                   name: stackube-config
                   key: kubernetes-port
           volumeMounts:
-            # mount as shared because mount propagation is not supported
-            # in kubernetes api yet.
-            - mountPath: /var/run/netns:shared
+            - mountPath: /var/run/netns
               name: netns
             - mountPath: /etc/ssl/certs
               name: certs
@@ -165,4 +163,4 @@ apiVersion: v1
 kind: ServiceAccount
 metadata:
   name: stackube-proxy
-  namespace: kube-system
+  namespace: kube-system