A few years ago, many of the top flight literary critics devoted a great deal of space to welcoming a first novel by a new, young writer. The novel was What Makes Sammy Run, and the author was Bud Schulberg. Two weeks ago, there appeared a new book by the same author, and it's called The Harder They Fall. It's a hard-hitting story of the prize fight business, or in the words of the publishers the fight racket.