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/fetchrepoorcz/default.nix

@@ -0,0 +1,10 @@
+{ fetchzip }:
+
+# gitweb example, snapshot support is optional in gitweb
+{ repo, rev, name ? "source"
+, ... # For hash agility
+}@args: fetchzip ({
+  inherit name;
+  url = "https://repo.or.cz/${repo}.git/snapshot/${rev}.tar.gz";
+  meta.homepage = "https://repo.or.cz/${repo}.git/";
+} // removeAttrs args [ "repo" "rev" ]) // { inherit rev; }