common/cpu/intel: add vaapi/vdpau drivers

I've tested this to work on MacBookAir4,1 and I'm going to deploy it
to MacBookAir6,2 today and Lenovo ThinkPad X230 in a week from now.
Also, cleaned up Lenovo ThinkPad X230 profile.

common/cpu/intel/default.nix

@@ -1,4 +1,12 @@
+{ lib, pkgs, ... }:
+
 {
-  hardware.cpu.intel.updateMicrocode = true;
+  hardware.cpu.intel.updateMicrocode = lib.mkDefault true;
   services.xserver.videoDrivers = [ "intel" ];
+
+  hardware.opengl.extraPackages = with pkgs; [
+    vaapiIntel
+    vaapiVdpau
+    libvdpau-va-gl
+  ];
 }

lenovo/thinkpad/x230/default.nix

@@ -1,24 +1,18 @@
 { config, lib, pkgs, ... }:
 
-with lib; {
+{
   imports = [
     ../.
     ../../../common/cpu/intel
   ];
 
   boot = {
+    extraModulePackages = with config.boot.kernelPackages; [
+      acpi_call
+    ];
     kernelModules = [
       "acpi_call"
       "tpm-rng"
     ];
-    extraModulePackages = with config.boot.kernelPackages; [
-      acpi_call
-    ];
   };
-
-  hardware.opengl.extraPackages = with pkgs; [
-    vaapiIntel
-    vaapiVdpau
-    libvdpau-va-gl
-  ];
 }