ox-texinfo: Fix @ref without description

* lisp/ox-texinfo.el (org-texinfo--@ref): Prefer @ref{} with a single
  argument when no description is provided.

lisp/ox-texinfo.el

@@ -1035,15 +1035,17 @@ CONTENTS is nil.  INFO is a plist holding contextual information."
 
 (defun org-texinfo--@ref (datum description info)
   "Return @ref command for element or object DATUM.
-DESCRIPTION is the name of the section to print, as a string."
+DESCRIPTION is the printed name of the section, as a string, or
+nil."
   (let ((node-name (org-texinfo--get-node datum info))
 	;; Sanitize DESCRIPTION for cross-reference use.  In
-	;; particular, remove colons as they seem to cause (even
-	;; within @asis{...} to the Texinfo reader.
-	(title (replace-regexp-in-string
-		"[ \t]*:+" ""
-		(replace-regexp-in-string "," "@comma{}" description))))
-    (if (equal title node-name)
+	;; particular, remove colons as they seem to cause pain (even
+	;; within @asis{...}) to the Texinfo reader.
+	(title (and description
+		    (replace-regexp-in-string
+		     "[ \t]*:+" ""
+		     (replace-regexp-in-string "," "@comma{}" description)))))
+    (if (or (not title) (equal title node-name))
 	(format "@ref{%s}" node-name)
       (format "@ref{%s, , %s}" node-name title))))
 
@@ -1091,20 +1093,8 @@ INFO is a plist holding contextual information.  See
 			       (org-element-type
 				(org-element-property :parent destination))))))
 	   (let ((headline (org-element-lineage destination '(headline) t)))
-	     (org-texinfo--@ref
-	      headline
-	      (or desc (org-texinfo--sanitize-title
-			(org-element-property :title headline) info))
-	      info)))
-	  (_
-	   (org-texinfo--@ref
-	    destination
-	    (or desc
-		(pcase (org-export-get-ordinal destination info)
-		  ((and (pred integerp) n) (number-to-string n))
-		  ((and (pred consp) n) (mapconcat #'number-to-string n "."))
-		  (_ "???")))		;cannot guess the description
-	    info)))))
+	     (org-texinfo--@ref headline desc info)))
+	  (_ (org-texinfo--@ref destination desc info)))))
      ((string= type "mailto")
       (format "@email{%s}"
 	      (concat (org-texinfo--sanitize-content path)