uboot: (firmwareOdroidC2/C4) don't invoke patch tool, use patches = [] instead

https://github.com/NixOS/nixpkgs/blob/master/pkgs/stdenv/generic/setup.sh#L948
this can do it nicely.

Signed-off-by: Anton Arapov <anton@deadbeef.mx>

pkgs/applications/misc/pdfdiff/default.nix

@@ -0,0 +1,39 @@
+{ lib, python2Packages, fetchurl, xpdf }:
+
+python2Packages.buildPythonApplication rec {
+  pname = "pdfdiff";
+  version = "0.92";
+
+  src = fetchurl {
+    url = "https://www.cs.ox.ac.uk/people/cas.cremers/downloads/software/pdfdiff.py";
+    sha256 = "0zxwjjbklz87wkbhkmsvhc7xmv5php7m2a9vm6ydhmhlxsybf836";
+  };
+
+  buildInputs = [  python2Packages.wrapPython ];
+
+  dontConfigure = true;
+  dontBuild = true;
+  doCheck = false;
+
+  unpackPhase = "cp $src pdfdiff.py";
+
+  postPatch = ''
+    sed -i -r 's|pdftotextProgram = "pdftotext"|pdftotextProgram = "${xpdf}/bin/pdftotext"|' pdfdiff.py
+    sed -i -r 's|progName = "pdfdiff.py"|progName = "pdfdiff"|' pdfdiff.py
+    '';
+
+  installPhase = ''
+    mkdir -p $out/bin
+    cp pdfdiff.py $out/bin/pdfdiff
+    chmod +x $out/bin/pdfdiff
+
+    substituteInPlace $out/bin/pdfdiff --replace "#!/usr/bin/python" "#!${python2Packages.python.interpreter}"
+    '';
+
+  meta = with lib; {
+    homepage = "http://www.cs.ox.ac.uk/people/cas.cremers/misc/pdfdiff.html";
+    description = "Tool to view the difference between two PDF or PS files";
+    license = licenses.gpl2Plus;
+    platforms = platforms.linux;
+  };
+}