Remove org-export-odt-use-bookmarks-for-internal-link

* contrib/lisp/org-odt.el
(org-export-odt-use-bookmarks-for-internal-links): Removed
unused variable.

contrib/lisp/org-odt.el

@@ -209,11 +209,6 @@ a per-file basis.  For example,
 
 (defconst org-export-odt-tmpdir-prefix "odt-")
 (defconst org-export-odt-bookmark-prefix "OrgXref.")
-(defcustom org-export-odt-use-bookmarks-for-internal-links t
-  "Export Internal links as bookmarks?."
-  :type 'boolean
-  :group 'org-export-odt)
-
 (defcustom org-export-odt-embed-images t
   "Should the images be copied in to the odt file or just linked?"
   :type 'boolean