Yes, the Oscar fashion race is heating up — with designers like Diane Von Furstenberg, Roberto Cavalli, James Purcell, Halston’s Craig Natiello, Randolph Duke, Mark Badgley and James Mischka, Christina Perrin and the Missonis heading to L.A. themselves, and reps for Vera Wang, Calvin Klein and Prada arriving any minute. But when Azzedine Alaia’s going to the Oscars, it’s a whole other ball game. It turns out the diminutive French designer is creating a couture gown for Stephanie Seymour, who will accompany her husband, Peter Brandt — who produced “Pollock” — down the Academy Awards red carpet. Alaia, like the father of the bride, will be walking the carpet right beside his muse.