Add support to enable FrSky telemetry on TELEM2

ROMFS/px4fmu_common/init.d/rcS

@@ -510,6 +510,10 @@ then
 	else
 		# XXX We need a better way for runtime eval of shell variables,
 		# but this works for now
+		if param compare SYS_COMPANION 10
+		then
+			frsky_telemetry start -d /dev/ttyS2
+		fi
 		if param compare SYS_COMPANION 921600
 		then
 			mavlink start -d /dev/ttyS2 -b 921600 -m onboard -r 80000 -x

src/modules/systemlib/system_params.c

@@ -105,6 +105,8 @@ PARAM_DEFINE_INT32(SYS_MC_EST_GROUP, 0);
  * companion computer interface.
  * Set to zero to disable, set to these values to enable (NO OTHER VALUES SUPPORTED!).
  *
+ * @value 0 Disabled
+ * @value 10 FrSky Telemetry
  * @value 921600 Companion Link (921600 baud, 8N1)
  * @value 57600 Companion Link (57600 baud, 8N1)
  * @value 157600 OSD (57600 baud, 8N1)