netperf: update source

pkgs/applications/networking/netperf/default.nix

···
-{stdenv, fetchurl}:
+{ stdenv, fetchFromGitHub }:
 
 stdenv.mkDerivation rec {
   name = "netperf-2.7.0";
 
-  src = fetchurl {
-    url = "ftp://ftp.netperf.org/netperf/${name}.tar.bz2";
-    sha256 = "0nip8178pdry0pqx2gkz0sl2gcvc7qww621q43kqnp43amvg2al4";
+  src = fetchFromGitHub {
+    owner = "HewlettPackard";
+    repo = "netperf";
+    rev = name;
+    sha256 = "034indn3hicwbvyzgw9f32bv2i7c5iv8b4a11imyn03pw97jzh10";
   };
 
   meta = {