Devotees of a South Bronx cockfighting den shut by cops this weekend predict the operation will be back in business in days. "It's big money," said a patron of the second-floor cockfighting den yesterday. "They'll be back next week, I guarantee it. If not in the same place, somewhere else in the neighborhood." Four of the men arrested this weekend were busted in a similar raid on a cockfighting arena in January. Cockfight clubs, like the one on Longwood Ave. that was raided Sunday, often relocate and reopen for business quickly after a bust, said authorities and fans of the...