By Matt Hladik The USFL season is over, but a number of players from the rebooted league are busy trying to find their way onto an NFL roster. The Pittsburgh Steelers in particular worked out five defensive linemen who played in the USFL this spring, according to ESPN’s Field Yates. Yates said that defensive tackles Doug Costin, Domenique Davis, Dondrea Tillman and Willie Yarbary, as well as defensive end Freedom Akinmoladun all tried out for the Steelers on Monday. Out of that group, two players (Costin and Akinmoladun) have NFL experience. Costin played in one game for the Jaguars last seaso…