Bo Nix was the last of the six quarterbacks picked in the first round of April’s NFL Draft. And the Broncos rookie enjoyed a preseason debut that might have bettered at least four selected before him. The Broncos used three quarterbacks in its win against the Colts.Jarrett Stidham received the start, then gave way to Nix, who, coincidentally, followed him at Auburn. (Obviously, before Nix transferred to Oregon). Then Zach Wilson finished the game. Preseason contests often see a stream of players headed into and out of a game as coaches figure out a new roster for the fall. Results don’t count …