serial: crisv10: fix invalid user-pointer check

Drop invalid user-pointer check from TIOCGSERIAL handler.

A NULL-pointer can be valid in user space and copy_to_user() takes care
of sanity checking.

Cc: Mikael Starvik <starvik@axis.com>
Cc: linux-cris-kernel@axis.com
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/crisv10.c

@@ -3213,8 +3213,6 @@ get_serial_info(struct e100_serial * info,
 	 * should set them to something else than 0.
 	 */
 
-	if (!retinfo)
-		return -EFAULT;
 	memset(&tmp, 0, sizeof(tmp));
 	tmp.type = info->type;
 	tmp.line = info->line;