Jimmy Fallon really loves to Neil Young-ify pop songs. After past efforts with “Whip My Hair” and “Party in the USA,” the “Tonight Show” host returned with a new cover. The musical choice? Song of the summer candidate “Fancy,” by Iggy Azalea and Charli XCX. While previous onstage companions have included Bruce Springsteen and Neil himself, Fallon made do this time with the rest of Young’s band, as Stills, Crosby and Nash all showed up to sing “let’s get drunk on the minibar.”