SERIES PREMIERE: Denis Leary’s new FX series, after the terrific Rescue Me, allows him to hit the same strong suits he explored on that firefighting series: the close-quarters camaraderie of guys when they tease and irritate one another, and the often very different perspectives and approaches of men and women in both professional and personal circumstances. In this new series, Leary plays Johnny Rock, a once, and briefly, famous rock singer, John Corbett plays his former lead guitarist, a