rtc: Convert to devm_ioremap_resource()

Convert all uses of devm_request_and_ioremap() to the newly introduced
devm_ioremap_resource() which provides more consistent error handling.

devm_ioremap_resource() provides its own error messages so all explicit
error messages can be removed from the failure code paths.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/rtc/rtc-s3c.c b/drivers/rtc/rtc-s3c.c
index 4046514..0c397ac 100644
--- a/drivers/rtc/rtc-s3c.c
+++ b/drivers/rtc/rtc-s3c.c
@@ -486,11 +486,9 @@
 		return -ENOENT;
 	}
 
-	s3c_rtc_base = devm_request_and_ioremap(&pdev->dev, res);
-	if (s3c_rtc_base == NULL) {
-		dev_err(&pdev->dev, "failed to ioremap memory region\n");
-		return -EINVAL;
-	}
+	s3c_rtc_base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(s3c_rtc_base))
+		return PTR_ERR(s3c_rtc_base);
 
 	rtc_clk = devm_clk_get(&pdev->dev, "rtc");
 	if (IS_ERR(rtc_clk)) {