org-agenda.el: Partially revert 19676dce

* lisp/org-agenda.el (org-agenda-show-new-time): Don't use
`org-agenda-previous-line'.

Thanks to Matt Lundin for reporting this.

lisp/org-agenda.el

@@ -9584,7 +9584,7 @@ Called with a universal prefix arg, show the priority instead of setting it."
 	   (list 'display (org-add-props stamp nil
 			    'face '(secondary-selection default))))
 	  (beginning-of-line 1))
-	(org-agenda-previous-line)))))
+	(beginning-of-line 0)))))
 
 (defun org-agenda-date-prompt (arg)
   "Change the date of this item.  Date is prompted for, with default today.