clisp hg: remove tohl from meta.maintainers list

Because tohl disappeared (last seen 2021-01-28).

pkgs/development/interpreters/clisp/hg.nix

···
   meta = {
     description = "ANSI Common Lisp Implementation";
     homepage = "http://clisp.cons.org";
-    maintainers = with lib.maintainers; [raskin tohl];
+    maintainers = with lib.maintainers; [ raskin ];
     # problems on Darwin: https://github.com/NixOS/nixpkgs/issues/20062
     platforms = lib.platforms.linux;
   };