cpython: Use autoreconfHook to rebuild configure script.

In particular this will let us use patches that apply to configure.ac.

pkgs/development/interpreters/python/cpython/2.7/default.nix

@@ -12,6 +12,7 @@
 , zlib
 , self
 , configd, coreutils
+, autoreconfHook
 , python-setup-hook
 # Some proprietary libs assume UCS2 unicode, especially on darwin :(
 , ucsEncoding ? 4
@@ -186,7 +187,8 @@ let
     ++ optionals x11Support [ tcl tk xlibsWrapper libX11 ]
     ++ optional (stdenv.isDarwin && configd != null) configd;
   nativeBuildInputs =
-    optionals (stdenv.hostPlatform != stdenv.buildPlatform)
+    [ autoreconfHook ]
+    ++ optionals (stdenv.hostPlatform != stdenv.buildPlatform)
       [ buildPackages.stdenv.cc buildPackages.python ];
 
   mkPaths = paths: {

pkgs/development/interpreters/python/cpython/default.nix

@@ -12,6 +12,7 @@
 , zlib
 , self
 , configd
+, autoreconfHook
 , python-setup-hook
 , nukeReferences
 # For the Python package set
@@ -51,6 +52,7 @@ let
   version = with sourceVersion; "${major}.${minor}.${patch}${suffix}";
 
   nativeBuildInputs = [
+    autoreconfHook
     nukeReferences
   ] ++ optionals (stdenv.hostPlatform != stdenv.buildPlatform) [
     buildPackages.stdenv.cc