By Alek Arend If USC football was a stock, Colin Cowherd would be taking out a second mortgage to buy as much as he could. Why? Two names: Lincoln Riley and Caleb Williams. The Trojans have entered a new era this offseason. They hired Riley away from Oklahoma and then landed Williams via the transfer portal. It’s a strong start as USC attempts to revive itself and become a giant in the sport again. It’s tough to envision USC becoming that giant as soon as this upcoming season. The Trojans still have plenty of holes and may not get past either Utah or Oregon in the Pac-12. But make no mistake: …