On the morning of the day when he won the Academy Award, Dr. Haing S. Ngor was a busy man. Just after dawn, outside the Dorothy Chandler Pavilion, he was clicking off TV interviews, one after another: "A.M. Los Angeles," "Good Morning America." The fans in the bleachers, who had waited all night huddled in their sleeping bags, chanted "Haing! Haing!" He waved to them like a kid at his first prom.