hosts/framenix: reduce power consumption with proper PPD CPU + ABM

- patch PPD to properly set the powersave level for the spu as well
- enable adaptive backlight management at lowest level

inspired by 1cbeaa156b/packages/default.nix

hosts/framenix/default.nix

@@ -38,8 +38,13 @@ in
     }
     ];
 
-  # temporary workaround for white flickering graphics artefacts
-  boot.kernelParams = [ "amdgpu.sg_display=0" ];
+  boot.kernelParams = [ 
+    # temporary workaround for white flickering graphics artefacts
+    "amdgpu.sg_display=0"
+    # powersave
+    "amd_pstate=active"
+    "amdgpu.abmlevel=1" # adaptive backlight management
+  ];
 
   boot.loader = {
     systemd-boot.enable = true;