lisp/org.el: Don't use lexical scope for diary related evals

* lisp/org.el (org-diary-sexp-entry): Don't use lexical scope for eval
sexps.

This commit partially reverts 6d73cd34a.

Reported-by: Eric S Fraga <e.fraga@ucl.ac.uk>

lisp/org.el

@@ -15040,9 +15040,11 @@ D may be an absolute day number, or a calendar-type list (month day year)."
   (let* ((sexp `(let ((entry ,entry)
 		      (date ',d))
 		  ,(car (read-from-string sexp))))
-	 (result (if calendar-debug-sexp (eval sexp t)
+         ;; FIXME: Do not use (eval ... t) in the following sexp as
+         ;; diary vars are still using dynamic scope.
+	 (result (if calendar-debug-sexp (eval sexp)
 		   (condition-case nil
-		       (eval sexp t)
+		       (eval sexp)
 		     (error
 		      (beep)
 		      (message "Bad sexp at line %d in %s: %s"