gpio: gpio-stp-xway.c: fix checkpatch error

Fix :
 gpio/gpio-stp-xway.c:220: ERROR: trailing whitespace
Signed-off-by: NLaurent Navet <laurent.navet@gmail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpio-stp-xway.c

@@ -217,7 +217,7 @@ static int xway_stp_probe(struct platform_device *pdev)
 	chip->virt = devm_ioremap_resource(&pdev->dev, res);
 	if (IS_ERR(chip->virt))
 		return PTR_ERR(chip->virt);
-	
+
 	chip->gc.dev = &pdev->dev;
 	chip->gc.label = "stp-xway";
 	chip->gc.direction_output = xway_stp_dir_out;