MEMPHIS, Tenn. (AP) — Steve Cropper, the lean, soulful guitarist and songwriter who helped anchor the celebrated Memphis backing band Booker T. and the M.G.’s at Stax Records and co-wrote the classics “Green Onions,” ”(Sittin’ on) the Dock of the Bay” and “In the Midnight Hour,” has died. He was 84. Pat Mitchell Worley, president and CEO of the Soulsville Foundation, said Cropper’s family told her that Cropper died on Wednesday in Nashville. The foundation operates the Stax Museum of American