Rover: use should_log() for more log msgs

APMrover2/APMrover2.pde

@@ -824,7 +824,7 @@ static void update_GPS_50Hz(void)
         g_gps2->update();
         if (g_gps2->last_message_time_ms() != last_gps2_reading) {
             last_gps2_reading = g_gps2->last_message_time_ms();
-            if (g.log_bitmask & MASK_LOG_GPS) {
+            if (should_log(MASK_LOG_GPS)) {
                 DataFlash.Log_Write_GPS2(g_gps2);
             }
         }

APMrover2/commands_logic.pde

@@ -14,6 +14,11 @@ static bool verify_nav_wp(const AP_Mission::Mission_Command& cmd);
 static bool
 start_command(const AP_Mission::Mission_Command& cmd)
 {
+    // log when new commands start
+    if (should_log(MASK_LOG_CMD)) {
+        Log_Write_Cmd(cmd);
+    }
+
     // exit immediately if not in AUTO mode
     if (control_mode != AUTO) {
         return false;

APMrover2/system.pde

@@ -233,8 +233,9 @@ static void init_ardupilot()
 
 	startup_ground();
 
-	if (g.log_bitmask & MASK_LOG_CMD)
-			Log_Write_Startup(TYPE_GROUNDSTART_MSG);
+	if (should_log(MASK_LOG_CMD)) {
+        Log_Write_Startup(TYPE_GROUNDSTART_MSG);
+    }
 
     set_mode((enum mode)g.initial_mode.get());
 
@@ -328,8 +329,9 @@ static void set_mode(enum mode mode)
 			break;
 	}
 
-	if (g.log_bitmask & MASK_LOG_MODE)
+	if (should_log(MASK_LOG_MODE)) {
 		Log_Write_Mode();
+    }
 }
 
 /*