overlays: Create overlays

modules/hardware/video.nix

@@ -1,7 +1,5 @@
-{ config, ... }:
+{ pkgs, ... }:
 
-let
-  unstable = (import ../unstable.nix config);
-in {
-  environment.systemPackages = [ unstable.mesa ];
+{
+  environment.systemPackages = with pkgs; [ unstable.mesa ];
 }