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/services/network-filesystems/u9fs.nix

@@ -0,0 +1,78 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+let
+  cfg = config.services.u9fs;
+in
+{
+
+  options = {
+
+    services.u9fs = {
+
+      enable = mkOption {
+        type = types.bool;
+        default = false;
+        description = "Whether to run the u9fs 9P server for Unix.";
+      };
+
+      listenStreams = mkOption {
+        type = types.listOf types.str;
+        default = [ "564" ];
+        example = [ "192.168.16.1:564" ];
+        description = ''
+          Sockets to listen for clients on.
+          See <command>man 5 systemd.socket</command> for socket syntax.
+        '';
+      };
+
+      user = mkOption {
+        type = types.str;
+        default = "nobody";
+        description =
+          "User to run u9fs under.";
+      };
+
+      extraArgs = mkOption {
+        type = types.str;
+        default = "";
+        example = "-a none";
+        description =
+          ''
+            Extra arguments to pass on invocation,
+            see <command>man 4 u9fs</command>
+          '';
+      };
+
+    };
+
+  };
+
+  config = mkIf cfg.enable {
+
+    systemd = {
+      sockets.u9fs = {
+        description = "U9fs Listening Socket";
+        wantedBy = [ "sockets.target" ];
+        after = [ "network.target" ];
+        inherit (cfg) listenStreams;
+        socketConfig.Accept = "yes";
+      };
+      services."u9fs@" = {
+        description = "9P Protocol Server";
+        reloadIfChanged = true;
+        requires = [ "u9fs.socket" ];
+        serviceConfig =
+          { ExecStart = "-${pkgs.u9fs}/bin/u9fs ${cfg.extraArgs}";
+            StandardInput = "socket";
+            StandardError = "journal";
+            User = cfg.user;
+            AmbientCapabilities = "cap_setuid cap_setgid";
+          };
+      };
+    };
+
+  };
+
+}