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/libidn/default.nix

@@ -0,0 +1,42 @@
+{ fetchurl, lib, stdenv, libiconv }:
+
+stdenv.mkDerivation rec {
+  pname = "libidn";
+  version = "1.38";
+
+  src = fetchurl {
+    url = "mirror://gnu/libidn/${pname}-${version}.tar.gz";
+    sha256 = "sha256-3gC4QPdXzTuxTdmiDVk2RzI13cugbUvC2oBGVLi78PY=";
+  };
+
+  outputs = [ "bin" "dev" "out" "info" "devdoc" ];
+
+  hardeningDisable = [ "format" ];
+
+  buildInputs = lib.optional stdenv.isDarwin libiconv;
+
+  meta = {
+    homepage = "https://www.gnu.org/software/libidn/";
+    description = "Library for internationalized domain names";
+
+    longDescription = ''
+      GNU Libidn is a fully documented implementation of the
+      Stringprep, Punycode and IDNA specifications.  Libidn's purpose
+      is to encode and decode internationalized domain names.  The
+      native C, C\# and Java libraries are available under the GNU
+      Lesser General Public License version 2.1 or later.
+
+      The library contains a generic Stringprep implementation.
+      Profiles for Nameprep, iSCSI, SASL, XMPP and Kerberos V5 are
+      included.  Punycode and ASCII Compatible Encoding (ACE) via IDNA
+      are supported.  A mechanism to define Top-Level Domain (TLD)
+      specific validation tables, and to compare strings against those
+      tables, is included.  Default tables for some TLDs are also
+      included.
+    '';
+
+    license = lib.licenses.lgpl2Plus;
+    platforms = lib.platforms.all;
+    maintainers = with lib.maintainers; [ lsix ];
+  };
+}