Fix `org-store-link'

* lisp/org.el (org-store-link): Fix parameter to `completing-read',
  which expects a string, not a symbol.

Reported-by: "Stefan-W. Hahn" <stefan.hahn@s-hahn.de>

lisp/org.el

@@ -9679,7 +9679,8 @@ active region."
 			 (cdr (assoc-string
 			       (completing-read
 				"Which function for creating the link? "
-				(mapcar #'car results-alist) nil t name)
+				(mapcar #'car results-alist)
+				nil t (symbol-name name))
 			       results-alist)))
 		  t))))
 	(setq link (plist-get org-store-link-plist :link))