Plane: To add a judgment of 0 degrees longitude.

ArduPlane/ArduPlane.cpp

@@ -449,7 +449,7 @@ void Plane::update_GPS_10Hz(void)
             // We countdown N number of good GPS fixes
             // so that the altitude is more accurate
             // -------------------------------------
-            if (current_loc.lat == 0) {
+            if (current_loc.lat == 0 && current_loc.lng == 0) {
                 ground_start_count = 5;
 
             } else {

ArduPlane/navigation.cpp

@@ -63,7 +63,7 @@ void Plane::navigate()
         return;
     }
 
-    if (next_WP_loc.lat == 0) {
+    if (next_WP_loc.lat == 0 && next_WP_loc.lng == 0) {
         return;
     }