serial: imx: fix bogus dev_err

Only one of the two is really required, not both:
* have_rtscts or
* have_rtsgpio

In imx_rs485_config() this is done correctly, so RS485 is working,
just the error message is false.
Signed-off-by: Phil Eichinger <phil@zankapfel.net>
Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>
Fixes: b8f3bff0 ("serial: imx: Support common rs485 binding for RTS polarity"
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/imx.c

@@ -2093,7 +2093,7 @@ static int serial_imx_probe(struct platform_device *pdev)
 	uart_get_rs485_mode(&pdev->dev, &sport->port.rs485);
 
 	if (sport->port.rs485.flags & SER_RS485_ENABLED &&
-	    (!sport->have_rtscts || !sport->have_rtsgpio))
+	    (!sport->have_rtscts && !sport->have_rtsgpio))
 		dev_err(&pdev->dev, "no RTS control, disabling rs485\n");
 
 	imx_rs485_config(&sport->port, &sport->port.rs485);