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 <[e-mail]>
Cc: Greg Kroah-Hartman <[e-mail]>
Signed-off-by: Kefeng Wang <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/tty/serial/amba-pl011.c

···
 
 	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;