gpio / ACPI: fix returned error from acpi_dev_gpio_irq_get()

acpi_dev_gpio_irq_get() currently ignores the error returned
by acpi_get_gpiod_by_index() and overwrites it with -ENOENT.

Problem is this error can be -EPROBE_DEFER, which just blows
up some drivers when the module ordering is not correct.

Cc: stable@vger.kernel.org
Signed-off-by: David Arcari <darcari@redhat.com>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpiolib-acpi.c

@@ -653,14 +653,17 @@ int acpi_dev_gpio_irq_get(struct acpi_device *adev, int index)
 {
 	int idx, i;
 	unsigned int irq_flags;
+	int ret = -ENOENT;
 
 	for (i = 0, idx = 0; idx <= index; i++) {
 		struct acpi_gpio_info info;
 		struct gpio_desc *desc;
 
 		desc = acpi_get_gpiod_by_index(adev, NULL, i, &info);
-		if (IS_ERR(desc))
+		if (IS_ERR(desc)) {
+			ret = PTR_ERR(desc);
 			break;
+		}
 		if (info.gpioint && idx++ == index) {
 			int irq = gpiod_to_irq(desc);
 
@@ -679,7 +682,7 @@ int acpi_dev_gpio_irq_get(struct acpi_device *adev, int index)
 		}
 
 	}
-	return -ENOENT;
+	return ret;
 }
 EXPORT_SYMBOL_GPL(acpi_dev_gpio_irq_get);