spi/rockchip: remove redundant dev_err call in rockchip_spi_probe()

There is a error message within devm_ioremap_resource
already, so remove the dev_err call to avoid redundant
error message.

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Mark Brown <broonie@linaro.org>
diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c
index 05e18e9..47c9168 100644
--- a/drivers/spi/spi-rockchip.c
+++ b/drivers/spi/spi-rockchip.c
@@ -600,7 +600,6 @@
 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	rs->regs = devm_ioremap_resource(&pdev->dev, mem);
 	if (IS_ERR(rs->regs)) {
-		dev_err(&pdev->dev, "Failed to map SPI region\n");
 		ret =  PTR_ERR(rs->regs);
 		goto err_ioremap_resource;
 	}