darwin.stdenv: provide an SDK when cross-compiling

Static can rely on the standard cross-SDK because it will be a static
SDK when building for static targets.

pkgs/stdenv/adapters.nix

@@ -137,8 +137,6 @@ rec {
   # Best effort static binaries. Will still be linked to libSystem,
   # but more portable than Nix store binaries.
   makeStaticDarwin = stdenv: stdenv.override (old: {
-    # extraBuildInputs are dropped in cross.nix, but darwin still needs them
-    extraBuildInputs = [ pkgs.buildPackages.darwin.CF ];
     mkDerivationFromStdenv = withOldMkDerivation old (stdenv: mkDerivationSuper: args:
     (mkDerivationSuper args).overrideAttrs (prevAttrs: {
       NIX_CFLAGS_LINK = toString (prevAttrs.NIX_CFLAGS_LINK or "")

pkgs/stdenv/cross/default.nix

@@ -75,7 +75,7 @@ in lib.init bootStages ++ [
       baseStdenv = stdenvNoCC.override {
         # Old ones run on wrong platform
         extraBuildInputs = lib.optionals hostPlatform.isDarwin [
-          buildPackages.targetPackages.darwin.apple_sdk.frameworks.CoreFoundation
+          buildPackages.targetPackages.apple-sdk
         ];
 
         hasCC = !stdenvNoCC.targetPlatform.isGhcjs;