MXO One of L.A.’s most celebrated chefs is playing with fire. Wes Avila, founder of Guerrilla Tacos and the now-shuttered Angry Egret Dinette, just opened Mexican steakhouse MXO in Beverly Grove, where steaks and seafood are singed over mesquite and peach wood, salsas and tortillas hit the tables along with ceviches and sides such as stewy Mayocoba beans or salsa …