spi: spi_txx9.c: use resource_size()

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

drivers/spi/spi_txx9.c

@@ -376,12 +376,10 @@ static int __init txx9spi_probe(struct platform_device *dev)
 	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
 	if (!res)
 		goto exit_busy;
-	if (!devm_request_mem_region(&dev->dev,
-				     res->start, res->end - res->start + 1,
+	if (!devm_request_mem_region(&dev->dev, res->start, resource_size(res),
 				     "spi_txx9"))
 		goto exit_busy;
-	c->membase = devm_ioremap(&dev->dev,
-				  res->start, res->end - res->start + 1);
+	c->membase = devm_ioremap(&dev->dev, res->start, resource_size(res));
 	if (!c->membase)
 		goto exit_busy;