By Diane Bartz WASHINGTON (Reuters) – A U.S. judge on Friday ruled in favor of U.S. Sugar Corp’s plans to buy rival Imperial Sugar Co, rejecting a Justice Department argument that the proposed deal would drive up the price of sugar for households as well as for food and soda makers. The Justice Department said in a lawsuit filed last November that the $315 million deal would give U.S. Sugar, owner and member of a cooperative with three other companies, and American Sugar Refining, which sells under the Domino brand, some 75% of refined sugar sales in the U.S. southeast. U.S. Sugar said in a st…