Added mb12xx sensor enable. (#5164)

ROMFS/px4fmu_common/init.d/rcS

@@ -593,6 +593,12 @@ then
 		sf0x start
 	fi
 
+	# mb12xx sonar sensor
+	if param compare SENS_EN_MB12XX 1
+	then
+		mb12xx start
+	fi
+
 	if ver hwcmp PX4FMU_V4
 	then
 		frsky_telemetry start -d /dev/ttyS6

src/modules/sensors/sensor_params.c

@@ -3054,6 +3054,16 @@ PARAM_DEFINE_INT32(SENS_EN_LL40LS, 0);
  */
 PARAM_DEFINE_INT32(SENS_EN_SF0X, 0);
 
+/**
+ * Maxbotix Soanr (mb12xx)
+ *
+ * @reboot_required true
+ *
+ * @boolean
+ * @group Sensor Enable
+ */
+PARAM_DEFINE_INT32(SENS_EN_MB12XX, 0);
+
 /**
  * Set the minimum PWM for the MAIN outputs
  *