In Home Assistant, when Home Assistant MQTT-Auto-Discovery is active,
almost all Sensors of the auto-discovered Victron device in Home
Assistant become "unavailable" after a short time - except those
Sensors with frequent changes like battery voltage or panel voltage.
This patch introduces regular mqtt updates for all VE.Direct sensors
when MQTT-Auto-Discovery is enabled.
Signed-off-by: Martin Dummer <martin.dummer@gmx.net>
