serial: bfin_5xx: fix off-by-one with resource size

This doesn't cause any real bugs, but it should still be fixed.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/tty/serial/bfin_5xx.c

@@ -1304,8 +1304,7 @@ static int bfin_serial_probe(struct platform_device *pdev)
 			goto out_error_free_peripherals;
 		}
 
-		uart->port.membase = ioremap(res->start,
-			res->end - res->start);
+		uart->port.membase = ioremap(res->start, resource_size(res));
 		if (!uart->port.membase) {
 			dev_err(&pdev->dev, "Cannot map uart IO\n");
 			ret = -ENXIO;