All the hacks using a final pseudo state are now useless.

All the hacks using a final pseudo state are now useless.
* src/LR0.c (set_state_table): state_table holds exactly nstates.
* src/lalr.c (nLA): New.
(initialize_LA, compute_lookaheads, initialize_lookaheads): Use it
instead of lookaheadsp from the pseudo state (nstate + 1).