mfd: fix htc-egpio iomem resource handling using resource_size

Fixes an off-by-one error in the iomem resource mapping.

Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
diff --git a/drivers/mfd/htc-egpio.c b/drivers/mfd/htc-egpio.c
index 194df7b..aa266e1 100644
--- a/drivers/mfd/htc-egpio.c
+++ b/drivers/mfd/htc-egpio.c
@@ -286,7 +286,7 @@
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (!res)
 		goto fail;
-	ei->base_addr = ioremap_nocache(res->start, res->end - res->start);
+	ei->base_addr = ioremap_nocache(res->start, resource_size(res));
 	if (!ei->base_addr)
 		goto fail;
 	pr_debug("EGPIO phys=%08x virt=%p\n", (u32)res->start, ei->base_addr);