drivers/ata: use resource_size

Use the function resource_size, which reduces the chance of introducing
off-by-one errors in calculating the resource size.

The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@@
struct resource *res;
@@

- (res->end - res->start) + 1
+ resource_size(res)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/ata/pata_platform.c b/drivers/ata/pata_platform.c
index d8d743a..3f6ebc6 100644
--- a/drivers/ata/pata_platform.c
+++ b/drivers/ata/pata_platform.c
@@ -151,14 +151,14 @@
 	 */
 	if (mmio) {
 		ap->ioaddr.cmd_addr = devm_ioremap(dev, io_res->start,
-				io_res->end - io_res->start + 1);
+				resource_size(io_res));
 		ap->ioaddr.ctl_addr = devm_ioremap(dev, ctl_res->start,
-				ctl_res->end - ctl_res->start + 1);
+				resource_size(ctl_res));
 	} else {
 		ap->ioaddr.cmd_addr = devm_ioport_map(dev, io_res->start,
-				io_res->end - io_res->start + 1);
+				resource_size(io_res));
 		ap->ioaddr.ctl_addr = devm_ioport_map(dev, ctl_res->start,
-				ctl_res->end - ctl_res->start + 1);
+				resource_size(ctl_res));
 	}
 	if (!ap->ioaddr.cmd_addr || !ap->ioaddr.ctl_addr) {
 		dev_err(dev, "failed to map IO/CTL base\n");