[python] Update to MicroPython 1.9.4

python/src/extmod/virtpin.h

@@ -23,6 +23,8 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+#ifndef MICROPY_INCLUDED_EXTMOD_VIRTPIN_H
+#define MICROPY_INCLUDED_EXTMOD_VIRTPIN_H
 
 #include "py/obj.h"
 
@@ -41,3 +43,5 @@ void mp_virtual_pin_write(mp_obj_t pin, int value);
 
 // If a port exposes a Pin object, it's constructor should be like this
 mp_obj_t mp_pin_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *args);
+
+#endif // MICROPY_INCLUDED_EXTMOD_VIRTPIN_H