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>

nixos/modules/testing/minimal-kernel.nix

@@ -0,0 +1,28 @@
+{ config, pkgs, lib, ... }:
+
+let
+  configfile = builtins.storePath (builtins.toFile "config" (lib.concatStringsSep "\n"
+    (map (builtins.getAttr "configLine") config.system.requiredKernelConfig))
+  );
+
+  origKernel = pkgs.buildLinux {
+    inherit (pkgs.linux) src version stdenv;
+    inherit configfile;
+    allowImportFromDerivation = true;
+    kernelPatches = [ pkgs.kernelPatches.cifs_timeout_2_6_38 ];
+  };
+
+  kernel = origKernel // (derivation (origKernel.drvAttrs // {
+    configurePhase = ''
+      runHook preConfigure
+      mkdir ../build
+      make $makeFlags "''${makeFlagsArray[@]}" mrproper
+      make $makeFlags "''${makeFlagsArray[@]}" KCONFIG_ALLCONFIG=${configfile} allnoconfig
+      runHook postConfigure
+    '';
+  }));
+
+   kernelPackages = pkgs.linuxPackagesFor kernel;
+in {
+  boot.kernelPackages = kernelPackages;
+}