MADRID (Reuters) – Spanish construction company ACS said on Wednesday it has an exclusive agreement with two investment funds, GIP and Brookfield, for the potential acquisition of a majority stake in the highway business of the Italian infrastructure company Atlantia. It said in a statement it had not yet made a decision. Earlier on Wednesday, shares in Atlantia surged almost 9% after Bloomberg News reported the company chaired by Spanish tycoon Florentino Perez, was weighing an offer for the Italian roads and airports group in which the Benetton family is a major investor. (Reporting by Jesús…