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/text/dfmt/default.nix

@@ -0,0 +1,27 @@
+{ lib
+, python3
+}:
+
+let
+  inherit (python3.pkgs)
+    buildPythonApplication
+    fetchPypi
+    pythonOlder;
+in
+buildPythonApplication rec {
+  pname = "dfmt";
+  version = "1.2.0";
+  disabled = pythonOlder "3.7";
+
+  src = fetchPypi {
+    inherit pname version;
+    sha256 = "7af6360ca8d556f1cfe82b97f03b8d1ea5a9d6de1fa3018290c844b6566d9d6e";
+  };
+
+  meta = with lib; {
+    description = "Format paragraphs, comments and doc strings";
+    homepage = "https://github.com/dmerejkowsky/dfmt";
+    license = licenses.bsd3;
+    maintainers = with maintainers; [ cole-h ];
+  };
+}