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/development/libraries/librevisa/default.nix

@@ -0,0 +1,31 @@
+{ lib, stdenv, fetchurl, pkg-config, libusb1 }:
+
+# TODO: add VXI development files, for VXI-11 (TCPIP) support
+
+stdenv.mkDerivation rec {
+  pname = "librevisa";
+  version = "0.0.20130412";
+
+  src = fetchurl {
+    url = "http://www.librevisa.org/download/${pname}-${version}.tar.gz";
+    sha256 = "0bjzq23s3xzw0l9qx4l8achrx5id8xdd6r52lvdl4a28dxzbcfhq";
+  };
+
+  nativeBuildInputs = [ pkg-config ];
+  buildInputs = [ libusb1 ];
+
+  meta = with lib; {
+    description = "Implementation of the VISA standard (for instrument control)";
+    longDescription = ''
+      LibreVISA aims to be a compliant implementation of the VISA standard in a
+      free software library.
+
+      We currently support targets connected via USB, exposing the USBTMC
+      interface, and VXI-11 devices.
+    '';
+    homepage = "http://www.librevisa.org/";
+    license = licenses.gpl3Plus;
+    platforms = platforms.linux ++ platforms.darwin;
+    maintainers = [ maintainers.bjornfor ];
+  };
+}