Mindy Kaling has been asking lady-killer John Mayer for love advice. The pair had lunch at Koi in the Trump SoHo yesterday, and “The Office” actress Kaling, who stars in the new TV show “The Mindy Project,” was overheard discussing her love life. “Mindy was asking for John’s advice,” says a spy, “She said, ‘You have to tell me what you think! Please!’ ” While her voice was clearly audible, Mayer, who canceled his tour due to surgery on his vocal chords, was “practically whispering,” continues the spy.