Steve Coogan has griped, to comic effect, about escaping his most famous Brit-TV creation, failed talk-show nitwit and ABBA fan Alan Patridge. “Alan Patridge: Alpha Papa” is a comedy opening in August, which, if you’re not familiar with the several TV shows (which follow him from TV to ever-smaller radio markets as he fails his way out of media) is going to be a hard sell. But to his fans? Hilarious.