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/build-support/writers/aliases.nix

@@ -0,0 +1,35 @@
+lib: prev:
+
+let
+  # Removing recurseForDerivation prevents derivations of aliased attribute
+  # set to appear while listing all the packages available.
+  removeRecurseForDerivations = alias: with lib;
+    if alias.recurseForDerivations or false then
+      removeAttrs alias ["recurseForDerivations"]
+    else alias;
+
+  # Disabling distribution prevents top-level aliases for non-recursed package
+  # sets from building on Hydra.
+  removeDistribute = alias: with lib;
+    if isDerivation alias then
+      dontDistribute alias
+    else alias;
+
+  # Make sure that we are not shadowing something from
+  # writers.
+  checkInPkgs = n: alias: if builtins.hasAttr n prev
+                          then throw "Alias ${n} is still in writers"
+                          else alias;
+
+  mapAliases = aliases:
+    lib.mapAttrs (n: alias: removeDistribute
+                             (removeRecurseForDerivations
+                              (checkInPkgs n alias)))
+                     aliases;
+
+in
+mapAliases ({
+  /* Cleanup before 22.05, Added 2021-12-11 */
+  writePython2 = "Python 2 is EOL and the use of writers.writePython2 is deprecated.";
+  writePython2Bin = "Python 2 is EOL and the use of writers.writePython2Bin is deprecated.";
+})