meta: move mobile-nixos imports out of flake

This is part of making the flake easier to understand by separating
concerns a bit more.

flake.nix

@@ -30,7 +30,6 @@
     {
       self,
       nixpkgs,
-      mobile-nixos,
       ...
     }@attrs:
     let
@@ -113,16 +112,6 @@
           modules = [
             ./hosts/phone/configuration.nix
             ./hosts/phone/hardware-configuration.nix
-
-            mobile-nixos.nixosModules.pine64-pinephone
-            mobile-nixos.nixosModules.module-list
-
-            {
-              mobile.beautification = {
-                silentBoot = true;
-                splash = true;
-              };
-            }
           ];
         };
 

hosts/phone/configuration.nix

@@ -1,16 +1,10 @@
-{
+{ self, ... }:
-  self,
-  pkgs,
-  lib,
-  ...
-}:
 
 let
-  inherit (lib) mkIf mkForce;
   inherit (builtins) attrValues;
 in
 {
-  imports = attrValues self.nixosModules;
+  imports = attrValues self.nixosModules ++ attrValues self.inputs.mobile-nixos.nixosModules;
 
   nixpkgs = {
     overlays = with self.overlays; [ phinger-cursors ];
@@ -47,4 +41,9 @@ in
 
     phone.enable = true;
   };
+
+  mobile.beautification = {
+    silentBoot = true;
+    splash = true;
+  };
 }