simpleproxy: fix build (#381537)

pkgs/by-name/si/simpleproxy/package.nix

@@ -2,6 +2,7 @@
   lib,
   stdenv,
   fetchFromGitHub,
+  autoreconfHook,
 }:
 
 stdenv.mkDerivation rec {
@@ -16,6 +17,8 @@ stdenv.mkDerivation rec {
     sha256 = "1my9g4vp19dikx3fsbii4ichid1bs9b9in46bkg05gbljhj340f6";
   };
 
+  nativeBuildInputs = [ autoreconfHook ];
+
   meta = with lib; {
     homepage = "https://github.com/vzaliva/simpleproxy";
     description = "Simple TCP proxy";