cctools: only add libtool on native builds

libtool is not really needed and it interferes with
updateAutotoolsGnuConfigScriptsHook. So remove it when
cross-compiling, but leave it in native to preserve hashes.

pkgs/os-specific/darwin/cctools/port.nix

@@ -30,7 +30,12 @@ let
 
     outputs = [ "out" "dev" ];
 
-    nativeBuildInputs = [ autoconf automake libtool autoreconfHook ];
+    nativeBuildInputs = [ autoconf automake ]
+
+      # TODO: remove on next hash change, libtool is unnecessary with autoreconfHook
+      ++ stdenv.lib.optional (stdenv.targetPlatform == stdenv.hostPlatform) libtool
+
+      ++ [ autoreconfHook ];
     buildInputs = [ libuuid ]
       ++ stdenv.lib.optionals stdenv.isDarwin [ libcxxabi libobjc ]
       ++ stdenv.lib.optional enableTapiSupport libtapi;