CHAPEL HILL — P.J. Hairston has been inconsistent thoughout his sophomore season at North Carolina. But he has been consistently good, at least offensively, during the Tar Heels’ past two games. Hairston scored 15 points during the Heels’ victory last week against Georgia Tech. And he led UNC with 19 points during its 91-83 loss at N.C. State on Saturday night.