flambda-backend: Add some missing command line arguments to ocamlnat (#499)

Author: stedolan

driver/main_args.ml

@@ -1603,6 +1603,7 @@ module Make_opttop_options (F : Opttop_options) = struct
     mk_dparsetree F._dparsetree;
     mk_dtypedtree F._dtypedtree;
     mk_drawlambda F._drawlambda;
+    mk_dlambda F._dlambda;
     mk_drawclambda F._drawclambda;
     mk_dclambda F._dclambda;
     mk_dcmm_invariants F._dcmm_invariants;
@@ -1626,6 +1627,7 @@ module Make_opttop_options (F : Opttop_options) = struct
     mk_dinterval F._dinterval;
     mk_dstartup F._dstartup;
     mk_dump_pass F._dump_pass;
+    mk_extension F._extension;
   ]
 end;;