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/compilers/chicken/5/egg2nix.nix

@@ -0,0 +1,29 @@
+{ lib, eggDerivation, fetchFromGitHub, chickenEggs }:
+
+# Note: This mostly reimplements the default.nix already contained in
+# the tarball. Is there a nicer way than duplicating code?
+
+let
+  version = "c5-git";
+in
+eggDerivation {
+  src = fetchFromGitHub {
+    owner = "corngood";
+    repo = "egg2nix";
+    rev = "chicken-5";
+    sha256 = "1vfnhbcnyakywgjafhs0k5kpsdnrinzvdjxpz3fkwas1jsvxq3d1";
+  };
+
+  name = "egg2nix-${version}";
+  buildInputs = with chickenEggs; [
+    args matchable
+  ];
+
+  meta = {
+    description = "Generate nix-expression from CHICKEN scheme eggs";
+    homepage = "https://github.com/the-kenny/egg2nix";
+    license = lib.licenses.bsd3;
+    platforms = lib.platforms.unix;
+    maintainers = with lib.maintainers; [ corngood ];
+  };
+}