Ethan Shanfeld A24 released a trailer for “C’mon C’mon,” which premiered at the Telluride Film Festival and will open in theaters later this year.Helmed by Mike Mills, the Oscar-winning director behind “20th Century Women,” the films stars Joaquin Phoenix as Johnny, a middle-aged radio journalist who, when left to take care of his nephew (Woody Norman), embarks on a trip across the country to interview kids, asking them what they think about their lives and where the world is headed.Rounding