tty: amba-pl011: Don't complain on -EPROBE_DEFER when no irq

Don't complain on -EPROBE_DEFER when attempting to get the irq.
the driver probe will be retried later.

Cc: Russell King <linux@armlinux.org.uk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/amba-pl011.c

@@ -2582,7 +2582,8 @@ static int sbsa_uart_probe(struct platform_device *pdev)
 
 	ret = platform_get_irq(pdev, 0);
 	if (ret < 0) {
-		dev_err(&pdev->dev, "cannot obtain irq\n");
+		if (ret != -EPROBE_DEFER)
+			dev_err(&pdev->dev, "cannot obtain irq\n");
 		return ret;
 	}
 	uap->port.irq	= ret;