lex_demand: added a couple of missing cases for new demand type
'L'# -> read_em (Lazy : acc) (stepOn buf)
'A'# -> read_em (Abs : acc) (stepOn buf)
'V'# -> read_em (Eval : acc) (stepOn buf)
+ 'X'# -> read_em (Err : acc) (stepOn buf)
+ 'B'# -> read_em (Bot : acc) (stepOn buf)
')'# -> (reverse acc, stepOn buf)
'C'# -> do_call acc (stepOnBy# buf 2#)
'U'# -> do_unpack1 Drop Now acc (stepOnBy# buf 1#)