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/tasks/filesystems/exfat.nix

@@ -0,0 +1,13 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+{
+  config = mkIf (any (fs: fs == "exfat") config.boot.supportedFilesystems) {
+    system.fsPackages = if config.boot.kernelPackages.kernelOlder "5.7" then [
+      pkgs.exfat # FUSE
+    ] else [
+      pkgs.exfatprogs # non-FUSE
+    ];
+  };
+}