By Zelie Pollon SANTA FE, N.M., May 25 (Reuters) - Firefighters managed to protect the remaining homes in a southwestern New Mexico subdivision overnight, but some outlying buildings were engulfed by flames from a fire that burned on rough mountain terrain near the Arizona border. Two fires merged in the Gila National Forest on Thursday and consumed 12,000 additional acres (4,856 hectares) overnight, bringing the total burn area to 82,252 acres (33,286 hectares) with none of it contained, said Public Information Officer Iris Estes.