MFC r264317, r264864:

- Add the Asus USB-N10 NANO [1]
- Fix panic by adding mtx_assert() to urtwn_init_locked() and
  urtwn_stop_locked() [2]

Tested by:	Kuan-Chung Chiu <buganini@gmail.com> [1]
		Anthony Jenkins <scoobi_doo at yahoo dot com> [2]