President Sergio Mattarella on Friday lit the brazier from which the torch for next February's Winter Olympics in Milan-Cortina will be lit at a relay inauguration ceremony outside the presidential Quirinale Palace in Rome.     Mattarella received the Olympic flame, which was flown from Athens to Rome Thursday, from the president of the Milano Cortina Foundation, Giovanni Malagò, as the Frecce Tricolori aerobatics team flew by overhead, and voiced the hope that an Olympic truce could be