Stevie Nicks, Liam Gallagher of Oasis, and Neil Young. Photo: Getty Images Biopics that stretch through the entirety of a musician’s life can be a slog — or, even worse, sanitized through a greatest-hits lens to appease estates to get them across the finish line. Two recent films about fabled rock stars, however, smartly chose to deviate from the norm and zoom in on very specific parts of their protagonists’ lives, warts and all. Springsteen: Deliver Me From Nowhere focused on the somewhat