pkgs/top-level/stage.nix: fix allowVariants with variants set

pkgs/top-level/stage.nix

@@ -191,15 +191,19 @@ let
 
   aliases = self: super: lib.optionalAttrs config.allowAliases (import ./aliases.nix lib self super);
 
-  variants = import ./variants.nix {
-    inherit
-      lib
-      nixpkgsFun
-      stdenv
-      overlays
-      makeMuslParsedPlatform
-      ;
-  };
+  variants =
+    self: super:
+    lib.optionalAttrs config.allowVariants (
+      import ./variants.nix {
+        inherit
+          lib
+          nixpkgsFun
+          stdenv
+          overlays
+          makeMuslParsedPlatform
+          ;
+      } self super
+    );
 
   # stdenvOverrides is used to avoid having multiple of versions
   # of certain dependencies that were used in bootstrapping the