A deranged Hamptons man stabbed his wheelchair-bound mom more than 40 times before horrified cops opened fire to stop the vicious Mother’s Day attack, officials revealed Monday. Steven Eastwood, 28, was shot and killed by cops during the shocking Sunday afternoon attack , which has the elderly victim fighting for her life at a local hospital and three police officers “very shook,” Southampton police Chief James Kiernan told reporters. “There have been numerous incidents at this address over the