AntennaTracker: support setting just accel trim with preflight-cal

use param5==2

AntennaTracker/GCS_Mavlink.pde

@@ -601,17 +601,24 @@ void GCS_MAVLINK::handleMessage(mavlink_message_t* msg)
                 }
                 if (is_equal(packet.param4,1.0f)) {
                     // Cant trim radio
-                }
-#if !defined( __AVR_ATmega1280__ )
-                else if (is_equal(packet.param5,1.0f)) {
+                } else if (is_equal(packet.param5,1.0f)) {
                     float trim_roll, trim_pitch;
                     AP_InertialSensor_UserInteract_MAVLink interact(this);
                     if(ins.calibrate_accel(&interact, trim_roll, trim_pitch)) {
                         // reset ahrs's trim to suggested values from calibration routine
                         ahrs.set_trim(Vector3f(trim_roll, trim_pitch, 0));
                     }
+                } else if (is_equal(packet.param5,2.0f)) {
+                    // accel trim
+                    float trim_roll, trim_pitch;
+                    if(ins.calibrate_trim(trim_roll, trim_pitch)) {
+                        // reset ahrs's trim to suggested values from calibration routine
+                        ahrs.set_trim(Vector3f(trim_roll, trim_pitch, 0));
+                        result = MAV_RESULT_ACCEPTED;
+                    } else {
+                        result = MAV_RESULT_FAILED;
+                    }
                 }
-#endif
                 result = MAV_RESULT_ACCEPTED;
                 break;
             }