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/ksm.nix

@@ -0,0 +1,22 @@
+import ./make-test-python.nix ({ lib, ...} :
+
+{
+  name = "ksm";
+  meta = with lib.maintainers; {
+    maintainers = [ rnhmjoj ];
+  };
+
+  nodes.machine = { ... }: {
+    imports = [ ../modules/profiles/minimal.nix ];
+
+    hardware.ksm.enable = true;
+    hardware.ksm.sleep = 300;
+  };
+
+  testScript =
+    ''
+      machine.start()
+      machine.wait_until_succeeds("test $(</sys/kernel/mm/ksm/run) -eq 1")
+      machine.wait_until_succeeds("test $(</sys/kernel/mm/ksm/sleep_millisecs) -eq 300")
+    '';
+})