feat(hosts/orion): enable powersave for wifi

We setup a custom `steam.desktop` entry for our applications that makes
Steam run on the Nvidia graphics card. As a consequence, all processes
launched by steam will likewise offload their graphical rendering to the
discrete graphics card as well.

hosts/orion/modules/hardware.nix

@@ -1,9 +1,6 @@
 { pkgs, config, ... }:
 {
-  services.xserver.videoDrivers = [
+  services.xserver.videoDrivers = [ "nvidia" ];
-    "intel"
-    "nvidia"
-  ];
   environment.variables.VDPAU_DRIVER = "va_gl";
   hardware = {
     enableRedistributableFirmware = true;