[Helium Plugin]Stats collection issue when controller disconnect the device

If device don't respond to the echo message with-in 2 seconds, controller explictly disconnect the device. This can cause RPC failure exception, because plugin is in process of setting up the master role and the moment it tries to register the rpc, node is disconnected. This create a permanent damage and cause some stale entry in the stats manager, so even if device connects back, it does not start the stats collection.