gpio: mlxbf3: add an error code check in mlxbf3_gpio_probe

Clang static checker warning: Value stored to 'ret' is never read.
bgpio_init() returns error code if failed, it's better to add this
check.

Fixes: cd33f21 ("gpio: mlxbf3: Add gpio driver support")
Signed-off-by: Su Hui <suhui@nfschina.com>
[Bartosz: add the Fixes: tag]
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

Author: Su Hui

drivers/gpio/gpio-mlxbf3.c

@@ -215,6 +215,8 @@ static int mlxbf3_gpio_probe(struct platform_device *pdev)
 			gs->gpio_clr_io + MLXBF_GPIO_FW_DATA_OUT_CLEAR,
 			gs->gpio_set_io + MLXBF_GPIO_FW_OUTPUT_ENABLE_SET,
 			gs->gpio_clr_io + MLXBF_GPIO_FW_OUTPUT_ENABLE_CLEAR, 0);
+	if (ret)
+		return dev_err_probe(dev, ret, "%s: bgpio_init() failed", __func__);
 
 	gc->request = gpiochip_generic_request;
 	gc->free = gpiochip_generic_free;