mb/google/deltaur: Add low power idle table

Add low power idle table to notify EC system is entering s0ix.

BUG=none
TEST=Power button and keyboard backlight are off when suspending.

Signed-off-by: Eric Lai <ericr_lai@compal.corp-partner.google.com>
Change-Id: Icf4dffe2bd289c15854bbad914c3b34b307254ec
Reviewed-on: https://review.coreboot.org/c/coreboot/+/41494
Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/mainboard/google/deltaur/dsdt.asl

@@ -34,6 +34,9 @@ DefinitionBlock(
 	/* VPD support */
 	#include <vendorcode/google/chromeos/acpi/vpd.asl>
 
+	/* Low power idle table */
+	#include <soc/intel/common/acpi/lpit.asl>
+
 	/* Chrome OS Embedded Controller */
 	Scope (\_SB.PCI0.LPCB)
 	{