Report as “good” instead of “unknown” for MQTT binary sensor

[francisp (Francis)]

use strategy 2 :

Sonoff RF Bridge. Strategies for receiving data

Here are two strategies for receiving payloads published by a Sonoff RF Bridge (flashed with Tasmota firmware). Strategy 1: value_template In this strategy, all sensors are subscribed to the same topic published by the RF Bridge. The topic's structure depends on how you defined it when you configured *your* RF Bridge. This example will use `tele/RF_Bridge/RESULT`. Change that to whatever you have set for your Bridge. Because all sensors are subscribed to the same topic, a sensor will receive pa…

Works perfect.