Fix flexvolume deploy nits

Since stackube-controller need time to start,
we need to use hostnetwork.

Change-Id: I0d29f23b49f58a87ddb43f65657e3554c4608afa
Signed-off-by: mozhuli <21621232@zju.edu.cn>

deployment/flexvolume/flexvolume-ds.yaml

@@ -40,6 +40,7 @@ spec:
           [{"key": "dedicated", "value": "master", "effect": "NoSchedule" },
            {"key":"CriticalAddonsOnly", "operator":"Exists"}]
     spec:
+      hostNetwork: true
       securityContext: {}
       containers:
         - name: cinder-flexvolume