USB: serial: ark3116: remove redundant interrupt-urb check

Remove redundant check of num_interrupt_in which has already been
verified in probe (killing a NULL-urb would also have been fine).
Reviewed-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NJohan Hovold <johan@kernel.org>

drivers/usb/serial/ark3116.c

@@ -347,8 +347,8 @@ static void ark3116_close(struct usb_serial_port *port)
 	ark3116_write_reg(serial, UART_IER, 0);
 
 	usb_serial_generic_close(port);
-	if (serial->num_interrupt_in)
-		usb_kill_urb(port->interrupt_in_urb);
+
+	usb_kill_urb(port->interrupt_in_urb);
 }
 
 static int ark3116_open(struct tty_struct *tty, struct usb_serial_port *port)