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>

lib/tests/modules/disable-declare-enable.nix

@@ -0,0 +1,5 @@
+{ lib, ... }:
+
+{
+  disabledModules = [ ./declare-enable.nix ];
+}