The BMW driver whose ride was surrounded and trashed by a gang of bicyclists on Fifth Avenue was attacked in broad daylight while driving with his elderly mom — who screamed during their escape, “We’re going to die, they’re going to kill us!” Max Torgovnick, 36, recounted the harrowing run-in to The Post one day after it unfolded around 4 p.m. Tuesday at 21st Street and Fifth Avenue. “It’s something that I never expected to happen in New York City,” said Torgovnick, a lifelong city resident. “That’s something like you would see on the streets of a war zone. I...