NORMAN, Okla. — Nico Iamaleava completed 13 of 21 passes for 194 yards and a touchdown, No. 6 Tennessee rushed for 151 yards and another score and the Vols played lock-down defense in a 25-15 win at No. 15 Oklahoma Saturday night, giving Josh Heupel a happy homecoming at Oklahoma Memorial Stadium. Here’s how it happened, as it happened: First QuarterTennessee 3, Oklahoma 0 (3:45): Max Gilbert kicked a 27-yard field goal to open the scoring. Nico Iamaleava hit Bru McCoy on a slant on second down and McCoy did the rest, turning it into a 38-yard catch-and-run to set the Vols up with first-and-go…