gpio: pisosr: Use devm_gpiod_get_optional for gpio->load_gpio

gpio->load_gpio is optional, so use devm_gpiod_get_optional instead.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Andrew F. Davis <afd@ti.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/gpio/gpio-pisosr.c b/drivers/gpio/gpio-pisosr.c
index f9f1074..8b8bf8f 100644
--- a/drivers/gpio/gpio-pisosr.c
+++ b/drivers/gpio/gpio-pisosr.c
@@ -125,15 +125,12 @@
 	if (!gpio->buffer)
 		return -ENOMEM;
 
-	gpio->load_gpio = devm_gpiod_get(dev, "load", GPIOD_OUT_LOW);
+	gpio->load_gpio = devm_gpiod_get_optional(dev, "load", GPIOD_OUT_LOW);
 	if (IS_ERR(gpio->load_gpio)) {
 		ret = PTR_ERR(gpio->load_gpio);
-		if (ret != -ENOENT && ret != -ENOSYS) {
-			if (ret != -EPROBE_DEFER)
-				dev_err(dev, "Unable to allocate load GPIO\n");
-			return ret;
-		}
-		gpio->load_gpio = NULL;
+		if (ret != -EPROBE_DEFER)
+			dev_err(dev, "Unable to allocate load GPIO\n");
+		return ret;
 	}
 
 	mutex_init(&gpio->lock);