The Las Vegas Raiders added a potential starting quarterback when they signed Gardner Minshew to a two-year contract this offseason but they likely aren’t done yet. Aidan O’Connell and Minshew are the only quarterbacks on the roster right now. The Raiders will add another quarterback at some point. According to a March 11 report from The Athletic’s Vic Tafur, Las Vegas did kick the tires on a trade for Chicago Bears quarterback Justin Fields. The former first-round pick is going to be on the move this offseason but the Bears’ asking price is likely going down every day. Despite the Minshew signing, Fox Sports’ Michael Irvin, Keyshawn Johnson and Skip Bayless all…