init adjustments to ensure used topics are advertised early (primarily for logging)

- multi-EKF create each instance as soon as IMU & mag are advertised (before device id populated)

src/drivers/heater/heater.cpp

@@ -73,6 +73,8 @@ Heater::Heater() :
 	}
 
 #endif
+
+	_heater_status_pub.advertise();
 }
 
 Heater::~Heater()