Revert "org-e-html/org-e-odt: Autoload (org-export-define-backend ...)"

This reverts commit 830a0781a6903bf83937a20aa43fe92027833ce6.

contrib/lisp/org-e-html.el

@@ -51,7 +51,6 @@
 
 ;;; Define Back-End
 
-;;;###autoload
 (org-export-define-backend e-html
   ((bold . org-e-html-bold)
    (center-block . org-e-html-center-block)

contrib/lisp/org-e-odt.el

@@ -33,7 +33,6 @@
 
 ;;; Define Back-End
 
-;;;###autoload
 (org-export-define-backend e-odt
   ((bold . org-e-odt-bold)
    (center-block . org-e-odt-center-block)