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/applications/video/kodi/addons/addon-update-script/default.nix

@@ -0,0 +1,23 @@
+{ writeShellScript
+, nix
+, curl
+, gzip
+, xmlstarlet
+, common-updater-scripts
+}:
+
+{ attrPath }:
+
+let
+  url = "http://mirrors.kodi.tv/addons/matrix/addons.xml.gz";
+  updateScript = writeShellScript "update.sh" ''
+    set -ex
+
+    attrPath=$1
+    namespace=$(${nix}/bin/nix-instantiate $systemArg --eval -E "with import ./. {}; $attrPath.namespace" | tr -d '"')
+    version=$(${curl}/bin/curl -s -L ${url} | ${gzip}/bin/gunzip -c | ${xmlstarlet}/bin/xml select -T -t -m "//addons/addon[@id='$namespace']" -v @version)
+
+    ${common-updater-scripts}/bin/update-source-version "$attrPath" "$version"
+  '';
+in
+  [ updateScript attrPath ]