Tracker: add auto opts param

This adds a bitmask that can be used to allow scaning before a vehicle has been found in auto mode

AntennaTracker/Parameters.cpp

@@ -477,6 +477,14 @@ const AP_Param::Info Tracker::var_info[] = {
     // @Path: ../libraries/AP_Stats/AP_Stats.cpp
     GOBJECT(stats, "STAT",  AP_Stats),
 
+    // @Param: AUTO_OPTIONS
+    // @DisplayName: Auto mode options
+    // @Description: 1: Scan for unknown target
+    // @User: Standard
+    // @Values: 0:None, 1: Scan for unknown target in auto mode
+    // @Bitmask: 0:Scan for unknown target
+    GSCALAR(auto_opts,              "AUTO_OPTIONS",        0),
+
     // @Group:
     // @Path: ../libraries/AP_Vehicle/AP_Vehicle.cpp
     { AP_PARAM_GROUP, "", Parameters::k_param_vehicle, (const void *)&tracker, {group_info : AP_Vehicle::var_info} },

AntennaTracker/Parameters.h

@@ -124,6 +124,8 @@ public:
         k_param_initial_mode,
         k_param_disarm_pwm,
 
+        k_param_auto_opts,
+
         k_param_logger = 253, // 253 - Logging Group
 
         k_param_vehicle = 257, // vehicle common block of parameters
@@ -164,6 +166,7 @@ public:
     AP_Int16 gcs_pid_mask;
     AP_Int8  initial_mode;
     AP_Int8 disarm_pwm;
+    AP_Int8 auto_opts;
 
     // Waypoints
     //

AntennaTracker/mode_auto.cpp

@@ -6,7 +6,7 @@ void ModeAuto::update()
 {
     if (tracker.vehicle.location_valid) {
         update_auto();
-    } else if (tracker.target_set) {
+    } else if (tracker.target_set || (tracker.g.auto_opts.get() & (1 << 0)) != 0) {
         update_scan();
     }
 }