acpi: Bump FADT to revision 6

Some of the revision 4 FADT fields were already updated to ACPI
spec revision 6, but not all of them. In addition the advertised
FADT revision was 3.

Implement all fields as defined in version 6 and bump the advertised
FADT revision to 6.

Also set all used access_size fields and x_gpe0_blk to sane values
as Windows 10 verifies those fields starting with FADT revision 5.

Fixes: https://ticket.coreboot.org/issues/109

Tested on Windows 10.

Change-Id: Ic649040025cd09ed3e490a521439ca4e681afbbf
Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/39805
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Matt DeVillier <matt.devillier@gmail.com>
diff --git a/src/soc/intel/apollolake/acpi.c b/src/soc/intel/apollolake/acpi.c
index 82ef3f1..fbfe33f 100644
--- a/src/soc/intel/apollolake/acpi.c
+++ b/src/soc/intel/apollolake/acpi.c
@@ -167,7 +167,7 @@
 	fadt->x_pm_tmr_blk.space_id = 1;
 	fadt->x_pm_tmr_blk.bit_width = fadt->pm_tmr_len * 8;
 	fadt->x_pm_tmr_blk.addrl = ACPI_BASE_ADDRESS + PM1_TMR;
-
+	fadt->x_pm_tmr_blk.access_size = ACPI_ACCESS_SIZE_DWORD_ACCESS;
 
 	if (cfg->lpss_s0ix_enable)
 		fadt->flags |= ACPI_FADT_LOW_PWR_IDLE_S0;