The Naval Academy football team clinched its trip to the postseason in decisive fashion Saturday, rolling over South Alabama 42-14 in Annapolis to move to 6-4 on the year. The win guarantees Navy will finish its regular season at .500 or better, meaning it can accept a bid to the Bell Helicopter Armed Forces Bowl, which kicks off at 11:45 a.m. Eastern on Dec. 30 in Fort Worth, Texas. Navy’s set to face a team from the Mountain West Conference, though the Mids might not know which team until early December. Can’t swing a trip to Texas over the holidays?…