A Cook County jury has awarded $3.6 million to a man who injured his head and back after falling from an allegedly faulty staircase.The verdict came after a trial lasting several days to determine whether Superior Corporation of Illinois in Elk Grove Village should be held liable for its alleged negligence in maintaining a staircase that led to a loading dock the man had to access after a truck delivery.The verdict was returned Tuesday.Truck driver Mark Edelen, then 48, of Tinley Park, was making a delivery to the company …