LLVM-3.9: Use nativeBuildInputs instead of buildPackages

pkgs/development/compilers/llvm/3.9/clang/default.nix

···
-{ stdenv, fetch, libxml2, libedit, llvm, version, clang-tools-extra_src, python, buildPackages }:
+{ stdenv, fetch, cmake, libxml2, libedit, llvm, version, clang-tools-extra_src, python }:
 
 let
   gcc = if stdenv.cc.isGNU then stdenv.cc.cc else stdenv.cc.cc.gcc;
···
       mv clang-tools-extra-* $sourceRoot/tools/extra
     '';
 
-    buildInputs = [ buildPackages.cmake libedit libxml2 llvm python ];
+    nativeBuildInputs = [ cmake ];
+
+    buildInputs = [ libedit libxml2 llvm python ];
 
     cmakeFlags = [
       "-DCMAKE_CXX_FLAGS=-std=c++11"

pkgs/development/compilers/llvm/3.9/llvm.nix

···
 
   outputs = [ "out" ] ++ stdenv.lib.optional enableSharedLibraries "lib";
 
+  nativeBuildInputs = [
+    perl
+    cmake
+    python
+  ];
+
   buildInputs = [
-    buildPackages.perl
-    buildPackages.buildPackages.cmake
-    buildPackages.python
     groff
     libxml2
     libffi ]