WASHINGTON - The White House is quietly pushing a Dubai company to "significantly restructure" and partner up with a U.S. outfit to keep the port deal from sinking, sources told the Daily News yesterday. "It's in the hands of the company now. ... They're going to have to significantly restructure," said a Republican source familiar with White House expectations. A revamped deal to allow Dubai Ports World to take over six major U.S. ports - including Manhattan's cruise ship terminal and Newark's container depot - would have to be something along the lines of the Marine One contract. British- and...