Updates to PubSubClient break MQTT client/callback

[KAJETALK]

It looks like PubSubClient has updated code which break the SecuritySensor4ToMQTT code

What is required now by PubSubClient is the following:
PubSubClient (server, port, [callback], client, [stream])

Creates a fully configured client instance.
Parameters

server : the address of the server (IPAddress, uint8_t[] or const char[])
port : the port to connect to (int)
callback : optional a pointer to a message callback function called when a message arrives for a subscription created by this client.
client : an instance of Client, typically EthernetClient.
stream : optional an instance of Stream, used to store received messages. See the mqtt_stream example for more information.

I was able to get it to compile by changing the callback method to the following:

void callback(
  char* topic,
  byte* payload,
  unsigned int length) {

And changing the constructor to the following:

// Instantiate MQTT client
EthernetClient ethClient;
PubSubClient client(server, 1883, callback, ethClient);