Remove 4 data constructors with special treatment.

generator/primitives.ml

@@ -140,10 +140,6 @@ let builtin_constructors_table =
     "()", ("Coq.Init.Datatypes.tt", 0);
     "true", ("Coq.Init.Datatypes.true", 0);
     "false", ("Coq.Init.Datatypes.false", 0);
-    "Nil", ("Coq.Lists.List.nil", 1);
-    "Cons", ("Coq.Lists.List.cons", 1);
-    "OkaStream.Nil", ("Coq.Lists.List.nil", 1);
-    "OkaStream.Cons", ("Coq.Lists.List.cons", 1);
     ]
     (* --todo: add [Pervasives] as prefix *)