ATLANTIC CITY, N.J. — Jim Allen once worked for Donald Trump in Atlantic City. Now, the chairman of Hard Rock International is doing all he can to scrub the influence of the man who is now president of the United States from his signature casino. Hard Rock, the gambling arm of the Seminole Indian tribe of Florida, is working on a remake of the former Trump Taj Mahal casino, which the company bought in March for $50 million, for about 4 cents on the dollar from the $1.2 billion Trump spent to open it in 1990. This week, Allen revealed more details about Hard Rock’s plans for what Trump once described as “the eighth wonder of the world.” The company is upping its investment in the former Taj Mahal from $350 million to $500 million.