move impermanence input up the tree

system/impermanence/default.nix

@@ -1,16 +1,7 @@
-{ config, lib, self, ... }: {
+{ config, lib, ... }: {
 
-    options = {};
 
-    config = lib.mkMerge [
-
-        {
-            imports = [
-                self.inputs.impermanence.nixosModules.impermanence
-            ];   
-        }
-
-        (lib.mkIf config.disko.impermanent {
+    config = lib.mkIf config.disko.impermanent {
 
             fileSystems."/persist".neededForBoot = true;
             environment.persistence = {
@@ -32,6 +23,5 @@
             };
 
             programs.fuse.userAllowOther = true;
-        })
-    ];
+    };
 }