chickenPackages_{4,5}: recurseIntoAttrs

This prevents further evaluation regression for chickenPackages if they
are deprecated again. Since chickenPackages_4 and chickenPackages_5 are
extremely tiny package set, the cost of building one additional set on
hydra is probably fine.

pkgs/development/compilers/chicken/4/default.nix

···
-{ newScope } :
+{ lib, newScope } :
 let
   callPackage = newScope self;
 
···
     egg2nix = callPackage ./egg2nix.nix { };
   };
 
-in self
+in lib.recurseIntoAttrs self

pkgs/development/compilers/chicken/5/default.nix

···
-{ newScope } :
+{ lib, newScope } :
 let
   callPackage = newScope self;
 
···
     egg2nix = callPackage ./egg2nix.nix { };
   };
 
-in self
+in lib.recurseIntoAttrs self