ccl: create ccl symlink

Make it more intuitive for users to start ccl and avoid platform
dependent executable names.

https://github.com/NixOS/nixpkgs/issues/26934

pkgs/development/compilers/ccl/default.nix

@@ -68,6 +68,7 @@ stdenv.mkDerivation rec {
     mkdir -p "$out/bin"
     echo -e '#!/bin/sh\n'"$out/share/ccl-installation/${CCL_RUNTIME}"' "$@"\n' > "$out"/bin/"${CCL_RUNTIME}"
     chmod a+x "$out"/bin/"${CCL_RUNTIME}"
+    ln -s "$out"/bin/"${CCL_RUNTIME}" "$out"/bin/ccl
   '';
 
   meta = with stdenv.lib; {