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/misc/fstrim.nix

@@ -0,0 +1,46 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+let
+
+  cfg = config.services.fstrim;
+
+in {
+
+  options = {
+
+    services.fstrim = {
+      enable = mkEnableOption "periodic SSD TRIM of mounted partitions in background";
+
+      interval = mkOption {
+        type = types.str;
+        default = "weekly";
+        description = ''
+          How often we run fstrim. For most desktop and server systems
+          a sufficient trimming frequency is once a week.
+
+          The format is described in
+          <citerefentry><refentrytitle>systemd.time</refentrytitle>
+          <manvolnum>7</manvolnum></citerefentry>.
+        '';
+      };
+    };
+
+  };
+
+  config = mkIf cfg.enable {
+
+    systemd.packages = [ pkgs.util-linux ];
+
+    systemd.timers.fstrim = {
+      timerConfig = {
+        OnCalendar = cfg.interval;
+      };
+      wantedBy = [ "timers.target" ];
+    };
+
+  };
+
+  meta.maintainers = with maintainers; [ ];
+}