mailbox: omap: Make use of the helper function devm_platform_ioremap_resource()

Use the devm_platform_ioremap_resource() helper instead of
calling platform_get_resource() and devm_ioremap_resource()
separately
Signed-off-by: Cai Huoqing <caihuoqing@baidu.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

drivers/mailbox/omap-mailbox.c

@@ -699,7 +699,6 @@ static struct mbox_chan *omap_mbox_of_xlate(struct mbox_controller *controller,
 
 static int omap_mbox_probe(struct platform_device *pdev)
 {
-	struct resource *mem;
 	int ret;
 	struct mbox_chan *chnls;
 	struct omap_mbox **list, *mbox, *mboxblk;
@@ -776,8 +775,7 @@ static int omap_mbox_probe(struct platform_device *pdev)
 	if (!mdev)
 		return -ENOMEM;
 
-	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	mdev->mbox_base = devm_ioremap_resource(&pdev->dev, mem);
+	mdev->mbox_base = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(mdev->mbox_base))
 		return PTR_ERR(mdev->mbox_base);