omap1: mailbox: kill compile warning

use ioremap and remove unused variable to get rid
of compile warnings.

Signed-off-by: Felipe Balbi <felipe.balbi@nokia.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
diff --git a/arch/arm/mach-omap1/mailbox.c b/arch/arm/mach-omap1/mailbox.c
index caf889a..4f5b3da 100644
--- a/arch/arm/mach-omap1/mailbox.c
+++ b/arch/arm/mach-omap1/mailbox.c
@@ -146,7 +146,6 @@
 static int __devinit omap1_mbox_probe(struct platform_device *pdev)
 {
 	struct resource *res;
-	int ret = 0;
 
 	if (pdev->num_resources != 2) {
 		dev_err(&pdev->dev, "invalid number of resources: %d\n",
@@ -160,12 +159,18 @@
 		dev_err(&pdev->dev, "invalid mem resource\n");
 		return -ENODEV;
 	}
-	mbox_base = res->start;
+
+	mbox_base = ioremap(res->start, resource_size(res));
+	if (!mbox_base) {
+		dev_err(&pdev->dev, "ioremap failed\n");
+		return -ENODEV;
+	}
 
 	/* DSP IRQ */
 	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 	if (unlikely(!res)) {
 		dev_err(&pdev->dev, "invalid irq resource\n");
+		iounmap(mbox_base);
 		return -ENODEV;
 	}
 	mbox_dsp_info.irq = res->start;