x86/acpi_device: Add support for GPIO output polarity

Instead of hard-coding the polarity of the GPIO to active high/low,
accept it as a parameter in devicetree. This polarity can then be used
while calling into acpi_dp_add_gpio to determine the active low status
correctly.

BUG=chrome-os-partner:55988
BRANCH=None
TEST=Verified that correct polarity is set for reset-gpio on reef.

Change-Id: I4aba4bb8bd61799962deaaa11307c0c5be112919
Signed-off-by: Furquan Shaikh <furquan@chromium.org>
Reviewed-on: https://review.coreboot.org/16877
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Tested-by: build bot (Jenkins)
diff --git a/src/mainboard/intel/kunimitsu/devicetree.cb b/src/mainboard/intel/kunimitsu/devicetree.cb
index a5789b0..8dded98 100644
--- a/src/mainboard/intel/kunimitsu/devicetree.cb
+++ b/src/mainboard/intel/kunimitsu/devicetree.cb
@@ -303,7 +303,7 @@
 		device pci 1f.2 on  end # Power Management Controller
 		device pci 1f.3 on
 			chip drivers/generic/max98357a
-				register "sdmode_gpio" = "ACPI_GPIO_OUTPUT(GPP_E3)"
+				register "sdmode_gpio" = "ACPI_GPIO_OUTPUT_ACTIVE_HIGH(GPP_E3)"
 				register "device_present_gpio" = "GPP_E3"
 				register "device_present_gpio_invert" = "1"
 				device generic 0 on end