Takeoff - allow publishing NAN longitude and latitude

A NAN is interpreted in the FlightTaskAuto as a non-valid global coordinate and sets a local position.
If a zero is sent instead, the global coordinate is recognized as valid and will be executed.
This is a problem when the global position is gained for the first time after takeoff and that a valid global reference did not exist before

src/modules/navigator/takeoff.cpp

@@ -139,10 +139,10 @@ Takeoff::set_takeoff_position()
 			pos_sp_triplet->current.yaw = rep->current.yaw;
 		}
 
-		if (PX4_ISFINITE(rep->current.lat) && PX4_ISFINITE(rep->current.lon)) {
-			pos_sp_triplet->current.lat = rep->current.lat;
-			pos_sp_triplet->current.lon = rep->current.lon;
-		}
+		// Set the current latitude and longitude even if they are NAN
+		// NANs are handled in FlightTaskAuto.cpp
+		pos_sp_triplet->current.lat = rep->current.lat;
+		pos_sp_triplet->current.lon = rep->current.lon;
 
 		// mark this as done
 		memset(rep, 0, sizeof(*rep));