gpiolib / ACPI: allow passing GPIOF_ACTIVE_LOW for GpioInt resources

The ACPI GpioInt resources contain polarity field that is used to specify
whether the interrupt is active high or low. Since gpiolib supports
GPIOF_ACTIVE_LOW we can pass this information in the flags field in
acpi_find_gpio(), analogous to the DeviceTree version.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c
index 03187d0..ae0ffdc 100644
--- a/drivers/gpio/gpiolib-acpi.c
+++ b/drivers/gpio/gpiolib-acpi.c
@@ -253,6 +253,8 @@
 					      agpio->pin_table[0]);
 		lookup->info.gpioint =
 			agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT;
+		lookup->info.active_low =
+			agpio->polarity == ACPI_ACTIVE_LOW;
 	}
 
 	return 1;