Update `org-export-backends'

* lisp/org.el (org-export-backends): Update variable.  `infojs' was
  merged into ox-html and `freemind' was added.

lisp/org.el

@@ -489,8 +489,8 @@ depends on, if any."
 	      (const :tag "   md          Export buffer to Markdown format" md)
 	      (const :tag "   odt         Export buffer to ODT format" odt)
 	      (const :tag "   texinfo     Export buffer to Texinfo format" texinfo)
-	      (const :tag "   infojs:     Set up Sebastian Rose's JavaScript org-info.js" jsinfo)
 	      (const :tag "C  confluence  Export buffer to Confluence Wiki format" confluence)
+	      (const :tag "C  freemind    Export buffer to Freemind mindmap format" freemind)
 	      (const :tag "C  groff       Export buffer to Groff format" groff)
 	      (const :tag "C  koma-letter Export buffer to KOMA Scrlttrl2 format" koma-letter)
 	      (const :tag "C  taskjuggler Export buffer to TaskJuggler format" taskjuggler)))