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/syncthing-relay.nix

@@ -0,0 +1,26 @@
+import ./make-test-python.nix ({ lib, pkgs, ... }: {
+  name = "syncthing-relay";
+  meta.maintainers = with pkgs.lib.maintainers; [ delroth ];
+
+  nodes.machine = {
+    environment.systemPackages = [ pkgs.jq ];
+    services.syncthing.relay = {
+      enable = true;
+      providedBy = "nixos-test";
+      pools = [];  # Don't connect to any pool while testing.
+      port = 12345;
+      statusPort = 12346;
+    };
+  };
+
+  testScript = ''
+    machine.wait_for_unit("syncthing-relay.service")
+    machine.wait_for_open_port(12345)
+    machine.wait_for_open_port(12346)
+
+    out = machine.succeed(
+        "curl -sSf http://localhost:12346/status | jq -r '.options.\"provided-by\"'"
+    )
+    assert "nixos-test" in out
+  '';
+})