org-agenda.el (org-agenda-insert-diary-make-new-entry): Fix docstring

* org-agenda.el (org-agenda-insert-diary-make-new-entry): Fix
docstring.

Thanks to Nikolai Weibull for reporting this.

lisp/org-agenda.el

@@ -9448,9 +9448,9 @@ a timestamp can be added there."
   (if org-adapt-indentation (org-indent-to-column 2)))
 
 (defun org-agenda-insert-diary-make-new-entry (text)
-  "Make new entry as last child of current entry.
-Add TEXT as headline, and position the cursor in the second line so that
-a timestamp can be added there."
+  "Make a new entry with TEXT as the first child of the current subtree.
+Position the point in the line right after the new heading so
+that a timestamp can be added there."
   (let ((org-show-following-heading t)
 	(org-show-siblings t)
 	(org-show-hierarchy-above t)