plymouth: add breeze-plymouth as default theme

nixos/modules/services/x11/desktop-managers/plasma5.nix

@@ -193,16 +193,6 @@ in
         theme = mkDefault "breeze";
       };
 
-      boot.plymouth = {
-        theme = mkDefault "breeze";
-        themePackages = mkDefault [
-          (pkgs.breeze-plymouth.override {
-            nixosBranding = true;
-            nixosVersion = config.system.nixosRelease;
-          })
-        ];
-      };
-
       security.pam.services.kde = { allowNullPassword = true; };
 
       # Doing these one by one seems silly, but we currently lack a better

nixos/modules/system/boot/plymouth.nix

@@ -8,9 +8,14 @@ let
 
   cfg = config.boot.plymouth;
 
+  breezePlymouth = pkgs.breeze-plymouth.override {
+    nixosBranding = true;
+    nixosVersion = config.system.nixosRelease;
+  };
+
   themesEnv = pkgs.buildEnv {
     name = "plymouth-themes";
-    paths = [ plymouth ] ++ cfg.themePackages;
+    paths = [ plymouth breezePlymouth ] ++ cfg.themePackages;
   };
 
   configFile = pkgs.writeText "plymouthd.conf" ''
@@ -38,7 +43,7 @@ in
       };
 
       theme = mkOption {
-        default = "fade-in";
+        default = "breeze";
         type = types.str;
         description = ''
           Splash screen theme.