Sean Quinlivan, the head pro at Shinnecock Hills, has analyzed for The Post how the 156 players in the field at the U.S. Open should play each hole . The 51-year-old Quinlivan, who grew up in the southwest of Ireland, has been the head pro at Shinnecock for the past five years after spending the previous 12 years at Piping Rock on Long Island. Here’s his hole-by-hole look at the 7,440-yard, Par 70 championship course, which is hosting its sixth U.S. Open: No. 1 | Westward Ho Par 4, 399 yards “