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/tools/networking/cdpr/default.nix

@@ -0,0 +1,38 @@
+{ lib, stdenv, fetchurl, fetchpatch, libpcap }:
+
+stdenv.mkDerivation rec {
+  pname = "cdpr";
+  version = "2.4";
+
+  src = fetchurl {
+    url = "mirror://sourceforge/${pname}/${pname}/${version}/${pname}-${version}.tgz";
+    sha256 = "1idyvyafkk0ifcbi7mc65b60qia6hpsdb6s66j4ggqp7if6vblrj";
+  };
+  patches = [
+    # Pull fix pending upstream inclusion for gcc-10 compatibility:
+    #  https://sourceforge.net/p/cdpr/bugs/3/
+    (fetchurl {
+      name = "fno-common";
+      url = "https://sourceforge.net/p/cdpr/bugs/3/attachment/0001-cdpr-fix-build-on-gcc-10-fno-common.patch";
+      sha256 = "023cvkpc4ry1pbjd91kkwj4af3hia0layk3fp8q40vh6mbr14pnp";
+    })
+  ];
+
+  postPatch = ''
+    substituteInPlace Makefile --replace 'gcc' '"$$CC"'
+  '';
+
+  buildInputs = [ libpcap ];
+
+  installPhase = ''
+    install -Dm755 cdpr $out/bin/cdpr
+  '';
+
+  meta = with lib; {
+    description = "Cisco Discovery Protocol Reporter";
+    homepage = "http://cdpr.sourceforge.net/";
+    license = licenses.gpl2Plus;
+    platforms = platforms.unix;
+    maintainers = [ maintainers.sgo ];
+  };
+}