dialogs: Drop re-centering combined dialog on item change

Gives maybe a bit more smooth appearance.
Allows it to be moved away and not re-centered on change.

src/dialog.c

@@ -403,7 +403,6 @@ DialogArrange(Dialog * d, int resize)
 	DialogRedraw(d);
 	DialogUpdate(d);
 	d->resize = 0;
-	ArrangeEwinCentered(d->ewin);
      }
 }