Tracker: move responsibility for logging into library

AntennaTracker/sensors.cpp

@@ -30,9 +30,6 @@ void Tracker::update_compass(void)
 {
     if (AP::compass().enabled() && compass.read()) {
         ahrs.set_compass(&compass);
-        if (should_log(MASK_LOG_COMPASS)) {
-            logger.Write_Compass();
-        }
     }
 }
 

AntennaTracker/system.cpp

@@ -60,6 +60,7 @@ void Tracker::init_tracker()
 #endif // ENABLE_SCRIPTING
 
     // initialise compass
+    AP::compass().set_log_bit(MASK_LOG_COMPASS);
     AP::compass().init();
 
     // GPS Initialization