mailbox:armada-37xx-rwtm:remove duplicate print in armada_37xx_mbox_probe()

In this function,we don't need dev_err() message because when something
goes wrong,platform_get_irq() and devm_platform_ioremap_resource() have
print an error message itself, so we should remove duplicate dev_err().
Signed-off-by: NTang Bin <tangbin@cmss.chinamobile.com>
Signed-off-by: NJassi Brar <jaswinder.singh@linaro.org>

drivers/mailbox/armada-37xx-rwtm-mailbox.c

@@ -156,16 +156,12 @@ static int armada_37xx_mbox_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	mbox->base = devm_platform_ioremap_resource(pdev, 0);
-	if (IS_ERR(mbox->base)) {
-		dev_err(&pdev->dev, "ioremap failed\n");
+	if (IS_ERR(mbox->base))
 		return PTR_ERR(mbox->base);
-	}
 
 	mbox->irq = platform_get_irq(pdev, 0);
-	if (mbox->irq < 0) {
-		dev_err(&pdev->dev, "Cannot get irq\n");
+	if (mbox->irq < 0)
 		return mbox->irq;
-	}
 
 	mbox->dev = &pdev->dev;