Old flames. Photo-Illustration: Vulture; Photos: Steve Jennings/WireImage, Lorne Thomson/Redferns All of those crystal circles paid off. Stevie Nicks and Lindsey Buckingham are back to being on speaking terms, several years after an estrangement caused by Buckingham’s firing from Fleetwood Mac and decades of relishing the most tumultuous (and hot) relationship in rock history. The duo appeared in separate interviews for the newest episode of Song Exploder, where they discussed the Buckingham