THAT VOICE. WHITNEY HOUSTON, at just 12 years old, steps out of the church choir for her first solo and blows the roof off the place. At 15, called onstage by her mom, gospel singer Cissy Houston, she does the same thing—at Carnegie Hall. Months later Luther Vandross hears The Voice and offers to be her producer. At 19, as she prepares her first album, her mentor, record exec Clive Davis, is already talking about her as one for the ages. “There was Lena Horne,” he says. “There is Dionne Warwick. But if the mantle is to pass to somebody . . . who’s elegant, who’s sensuous, who’s innocent, who’s got an incredible range of talent . . . it will be Whitney Houston.” And, of course, he’s right. The…