remove duplicated scheduled tasks from VpcVirtualNetworkApplianceManagerImpl

(cherry picked from commit e444a03819)

server/src/com/cloud/network/router/VpcVirtualNetworkApplianceManagerImpl.java

@@ -1361,6 +1361,16 @@ public class VpcVirtualNetworkApplianceManagerImpl extends VirtualNetworkApplian
     public List<DomainRouterVO> getVpcRouters(long vpcId) {
         return _routerDao.listByVpcId(vpcId);
     }
+    
+    @Override
+    public boolean start() {
+        return true;
+    }
+    
+    @Override
+    public boolean stop() {
+        return true;
+    }    
 
     @Override
     public String[] applyVpnUsers(RemoteAccessVpn vpn, List<? extends VpnUser> users, VirtualRouter router) throws ResourceUnavailableException {