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/tests/nfs/default.nix

@@ -0,0 +1,9 @@
+{ version ? 4
+, system ? builtins.currentSystem
+, pkgs ? import ../../.. { inherit system; }
+}: {
+  simple = import ./simple.nix { inherit version system pkgs; };
+} // pkgs.lib.optionalAttrs (version == 4) {
+  # TODO: Test kerberos + nfsv3
+  kerberos = import ./kerberos.nix { inherit version system pkgs; };
+}