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/tools/misc/gnum4/default.nix

@@ -0,0 +1,50 @@
+{ lib, stdenv, fetchurl }:
+
+# 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 = "gnum4";
+  version = "1.4.19";
+
+  src = fetchurl {
+    url = "mirror://gnu/m4/m4-${version}.tar.bz2";
+    sha256 = "sha256-swapHA/ZO8QoDPwumMt6s5gf91oYe+oyk4EfRSyJqMg=";
+  };
+
+  strictDeps = true;
+  enableParallelBuilding = true;
+
+  doCheck = false;
+
+  configureFlags = [ "--with-syscmd-shell=${stdenv.shell}" ]
+    ++ lib.optional stdenv.hostPlatform.isMinGW "CFLAGS=-fno-stack-protector";
+
+  meta = {
+    description = "GNU M4, a macro processor";
+    longDescription = ''
+      GNU M4 is an implementation of the traditional Unix macro
+      processor.  It is mostly SVR4 compatible although it has some
+      extensions (for example, handling more than 9 positional
+      parameters to macros).  GNU M4 also has built-in functions for
+      including files, running shell commands, doing arithmetic, etc.
+
+      GNU M4 is a macro processor in the sense that it copies its
+      input to the output expanding macros as it goes.  Macros are
+      either builtin or user-defined and can take any number of
+      arguments.  Besides just doing macro expansion, m4 has builtin
+      functions for including named files, running UNIX commands,
+      doing integer arithmetic, manipulating text in various ways,
+      recursion etc...  m4 can be used either as a front-end to a
+      compiler or as a macro processor in its own right.
+    '';
+    homepage = "https://www.gnu.org/software/m4/";
+
+    license = lib.licenses.gpl3Plus;
+    mainProgram = "m4";
+    platforms = lib.platforms.unix ++ lib.platforms.windows;
+  };
+
+}