serial: core: lock port for stop_rx() in uart_suspend_port()

The uarts_ops stop_rx() callback expects that the port->lock is
taken and interrupts are disabled.

Fixes: c9d2325c ("serial: core: Do stop_rx in suspend path for console if console_suspend is disabled")
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20230525093159.223817-3-john.ogness@linutronix.deSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/serial_core.c

@@ -2333,8 +2333,11 @@ int uart_suspend_port(struct uart_driver *drv, struct uart_port *uport)
 	 * able to Re-start_rx later.
 	 */
 	if (!console_suspend_enabled && uart_console(uport)) {
-		if (uport->ops->start_rx)
+		if (uport->ops->start_rx) {
+			spin_lock_irq(&uport->lock);
 			uport->ops->stop_rx(uport);
+			spin_unlock_irq(&uport->lock);
+		}
 		goto unlock;
 	}