mmc: au1xmmc.c: use resource_size()

[cjb: rebased patch against Linus]
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: <linux-mmc@vger.kernel.org>
Acked-by: Manuel Lauss <manuel.lauss@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Chris Ball <cjb@laptop.org>

drivers/mmc/host/au1xmmc.c

@@ -964,7 +964,7 @@ static int __devinit au1xmmc_probe(struct platform_device *pdev)
 		goto out1;
 	}
 
-	host->ioarea = request_mem_region(r->start, r->end - r->start + 1,
+	host->ioarea = request_mem_region(r->start, resource_size(r),
 					   pdev->name);
 	if (!host->ioarea) {
 		dev_err(&pdev->dev, "mmio already in use\n");