Fix invalid offboard setpoints for fw pos control

This commit fixes a regression that disables offboard control

src/modules/fw_pos_control_l1/FixedwingPositionControl.cpp

@@ -2199,12 +2199,11 @@ FixedwingPositionControl::Run()
 					}
 				}
 
+				_position_setpoint_current_valid = valid_setpoint;
+
 				if (!valid_setpoint) {
 					events::send(events::ID("fixedwing_position_control_invalid_offboard_sp"), events::Log::Error,
 						     "Invalid offboard setpoint");
-
-				} else {
-					_pos_sp_triplet.current.valid = valid_setpoint;
 				}
 			}