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>

pkgs/tools/admin/berglas/default.nix

@@ -0,0 +1,49 @@
+{ lib, buildGoModule, fetchFromGitHub }:
+
+let
+  skipTests = {
+    access = "Access";
+    create = "Create";
+    delete = "Delete";
+    list = "List";
+    read = "Read";
+    replace = "Replace";
+    resolver = "Resolve";
+    revoke = "Revoke";
+    update = "Update";
+  };
+
+  skipTestsCommand =
+    builtins.foldl' (acc: goFileName:
+      let testName = builtins.getAttr goFileName skipTests; in
+      ''
+        ${acc}
+        substituteInPlace pkg/berglas/${goFileName}_test.go \
+          --replace "TestClient_${testName}_storage" "SkipClient_${testName}_storage" \
+          --replace "TestClient_${testName}_secretManager" "SkipClient_${testName}_secretManager"
+      ''
+    ) "" (builtins.attrNames skipTests);
+in
+
+buildGoModule rec {
+  pname = "berglas";
+  version = "0.6.2";
+
+  src = fetchFromGitHub {
+    owner = "GoogleCloudPlatform";
+    repo = pname;
+    rev = "v${version}";
+    sha256 = "sha256-aLsrrK+z080qn7L2zggA8yD+QqLaSRJLTjWQnFKFogQ=";
+  };
+
+  vendorSha256 = "sha256-HjZT0jezJzoEvXuzrjoTv/zSex+xDuGoP1h82CIlX14=";
+
+  postPatch = skipTestsCommand;
+
+  meta = with lib; {
+    description = "A tool for managing secrets on Google Cloud";
+    homepage = "https://github.com/GoogleCloudPlatform/berglas";
+    license = licenses.asl20;
+    platforms = platforms.unix;
+  };
+}