Best way to link a rpi_rf switch to a MQTT switch?

Configuration
1

I have a RF transmitter connected to my Pi that switches my fireplace on/off. I’d like to be able to control this from MQTT. Whats the best way to combine them? An automation or is there a simpler way just in the configuration file?

switch:
  - platform: rpi_rf
    gpio: 17
    switches:
      fireplace:
        protocol: 1
        pulselength: 384
        code_on: 1364422
        code_off: 1364408
  - platform: mqtt
    name: "Fireplace MQTT"
    state_topic: "smartthings/Fireplace/switch"
    command_topic: "smartthings/Fireplace/switch"
    payload_on: "on"
    payload_off: "off"
    retain: true