Ames, Iowa (AP) - Iowa State Head Football Coach Paul Rhoads has resigned effective immediately and is expected to take the head coaching job at Louisiana State University.  The LSU job was vacated earlier today when Les Miles accepted the top job at the University of Michigan, where he both played and coached.   "It's pretty clear to me," Rhoads told reporters. "Chizik left here after two years, goes to the SEC and wins a title. Look out Baton Rouge, we're gonna win it all!"   Cyclones Athletic Director Jamie Pollard was unavailable for comment, but a source inside the department said his mood was "inconsolable".