add RC kill switch

src/modules/sensors/sensor_params.c

@@ -2009,6 +2009,15 @@ PARAM_DEFINE_INT32(RC_MAP_ACRO_SW, 0);
  */
 PARAM_DEFINE_INT32(RC_MAP_OFFB_SW, 0);
 
+/**
+ * Kill switch channel mapping.
+ *
+ * @min 0
+ * @max 18
+ * @group Radio Switches
+ */
+PARAM_DEFINE_INT32(RC_MAP_KILL_SW, 0);
+
 /**
  * Flaps channel mapping.
  *
@@ -2243,6 +2252,25 @@ PARAM_DEFINE_FLOAT(RC_ACRO_TH, 0.5f);
  */
 PARAM_DEFINE_FLOAT(RC_OFFB_TH, 0.5f);
 
+
+/**
+ * Threshold for selecting offboard mode
+ *
+ * 0-1 indicate where in the full channel range the threshold sits
+ * 		0 : min
+ * 		1 : max
+ * sign indicates polarity of comparison
+ * 		positive : true when channel>th
+ * 		negative : true when channel<th
+ *
+ * @min -1
+ * @max 1
+ * @group Radio Switches
+ *
+ *
+ */
+PARAM_DEFINE_FLOAT(RC_KILLSWITCH_TH, 0.25f);
+
 /**
  * PWM input channel that provides RSSI.
  *