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/nixops/legacy/base-configuration.nix

@@ -0,0 +1,31 @@
+{ lib, modulesPath, pkgs, ... }:
+let
+  ssh-keys =
+    if builtins.pathExists ../../ssh-keys.nix
+    then # Outside sandbox
+      ../../ssh-keys.nix
+    else # In sandbox
+      ./ssh-keys.nix;
+
+  inherit (import ssh-keys pkgs)
+    snakeOilPrivateKey snakeOilPublicKey;
+in
+{
+  imports = [
+    (modulesPath + "/virtualisation/qemu-vm.nix")
+    (modulesPath + "/testing/test-instrumentation.nix")
+  ];
+  virtualisation.writableStore = true;
+  nix.settings.substituters = lib.mkForce [ ];
+  virtualisation.graphics = false;
+  documentation.enable = false;
+  services.qemuGuest.enable = true;
+  boot.loader.grub.enable = false;
+
+  services.openssh.enable = true;
+  users.users.root.openssh.authorizedKeys.keys = [
+    snakeOilPublicKey
+  ];
+  security.pam.services.sshd.limits =
+    [{ domain = "*"; item = "memlock"; type = "-"; value = 1024; }];
+}