packages: Use locales from the /X.Y sub-directory of the locale package.

This is a followup to commit f2d7bbb.

* guix/packages.scm (patch-and-repack)[build]: Append "/X.Y" to
  LOCPATH.

guix/packages.scm

@@ -477,7 +477,10 @@ IMPORTED-MODULES specify modules to use/import for use by SNIPPET."
           (when #+locales
             ;; First of all, install a UTF-8 locale so that UTF-8 file names
             ;; are correctly interpreted.  During bootstrap, LOCALES is #f.
-            (setenv "LOCPATH" (string-append #+locales "/lib/locale"))
+            (setenv "LOCPATH"
+                    (string-append #+locales "/lib/locale/"
+                                   #+(and locales
+                                          (package-version locales))))
             (setlocale LC_ALL "en_US.utf8"))
 
           (setenv "PATH" (string-append #+xz "/bin" ":"