gpio: pisosr: Simplify with dev_err_probe()

Common pattern of handling deferred probe can be simplified with
dev_err_probe().  Less code and also it prints the error value.

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>

drivers/gpio/gpio-pisosr.c

@@ -148,12 +148,9 @@ static int pisosr_gpio_probe(struct spi_device *spi)
 		return -ENOMEM;
 
 	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 != -EPROBE_DEFER)
-			dev_err(dev, "Unable to allocate load GPIO\n");
-		return ret;
-	}
+	if (IS_ERR(gpio->load_gpio))
+		return dev_err_probe(dev, PTR_ERR(gpio->load_gpio),
+				     "Unable to allocate load GPIO\n");
 
 	mutex_init(&gpio->lock);