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>

nixos/modules/config/appstream.nix

@@ -0,0 +1,25 @@
+{ config, lib, ... }:
+
+with lib;
+{
+  options = {
+    appstream.enable = mkOption {
+      type = types.bool;
+      default = true;
+      description = ''
+        Whether to install files to support the
+        <link xlink:href="https://www.freedesktop.org/software/appstream/docs/index.html">AppStream metadata specification</link>.
+      '';
+    };
+  };
+
+  config = mkIf config.appstream.enable {
+    environment.pathsToLink = [
+      # per component metadata
+      "/share/metainfo"
+      # legacy path for above
+      "/share/appdata"
+    ];
+  };
+
+}