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/libunistring/default.nix

@@ -0,0 +1,73 @@
+{ fetchurl, lib, stdenv, libiconv }:
+
+# Note: this package is used for bootstrapping fetchurl, and thus
+# cannot use fetchpatch! All mutable patches (generated by GitHub or
+# cgit) that are needed here should be included directly in Nixpkgs as
+# files.
+
+stdenv.mkDerivation rec {
+  pname = "libunistring";
+  version = "1.0";
+
+  src = fetchurl {
+    url = "mirror://gnu/libunistring/${pname}-${version}.tar.gz";
+    sha256 = "sha256-PAGEwOSS18IIzjHSXdHSxY8MPtbLvgMsWySM3a0xhUQ=";
+  };
+
+  outputs = [ "out" "dev" "info" "doc" ];
+
+  strictDeps = true;
+  propagatedBuildInputs = lib.optional (!stdenv.isLinux) libiconv;
+
+  configureFlags = [
+    "--with-libiconv-prefix=${libiconv}"
+  ];
+
+  doCheck = false;
+
+  /* This seems to cause several random failures like these, which I assume
+     is because of bad or missing target dependencies in their build system:
+
+        ./unistdio/test-u16-vasnprintf2.sh: line 16: ./test-u16-vasnprintf1: No such file or directory
+        FAIL unistdio/test-u16-vasnprintf2.sh (exit status: 1)
+
+        FAIL: unistdio/test-u16-vasnprintf3.sh
+        ======================================
+
+        ./unistdio/test-u16-vasnprintf3.sh: line 16: ./test-u16-vasnprintf1: No such file or directory
+        FAIL unistdio/test-u16-vasnprintf3.sh (exit status: 1)
+  */
+  enableParallelBuilding = false;
+
+  meta = {
+    homepage = "https://www.gnu.org/software/libunistring/";
+
+    description = "Unicode string library";
+
+    longDescription = ''
+      This library provides functions for manipulating Unicode strings
+      and for manipulating C strings according to the Unicode
+      standard.
+
+      GNU libunistring is for you if your application involves
+      non-trivial text processing, such as upper/lower case
+      conversions, line breaking, operations on words, or more
+      advanced analysis of text.  Text provided by the user can, in
+      general, contain characters of all kinds of scripts.  The text
+      processing functions provided by this library handle all scripts
+      and all languages.
+
+      libunistring is for you if your application already uses the ISO
+      C / POSIX <ctype.h>, <wctype.h> functions and the text it
+      operates on is provided by the user and can be in any language.
+
+      libunistring is also for you if your application uses Unicode
+      strings as internal in-memory representation.
+    '';
+
+    license = lib.licenses.lgpl3Plus;
+
+    maintainers = [ ];
+    platforms = lib.platforms.all;
+  };
+}