src: Drop useless PM1b settings from FADT

None of the currently-supported chips has PM1b_EVT nor PM1b_CNT event
register blocks. According to the ACPI specification, version 6.3,
sections 4.8.1.1 and 4.8.1.2 (PM1 Event/Control Registers):

 If the PM1b_EVT_BLK is not supported, its pointer contains a value of
 zero in the FADT.

 If the PM1b_CNT_BLK is not supported, its pointer contains a value of
 zero in the FADT.

Since the FADT struct defaults to zero in coreboot, we don't need to do
anything with PM1b for now. So, drop unneeded writes to PM1b fields.

Tested on Asus P8Z77-V LX2 with Linux 5.7.6 and Windows 10 at the end of
the patch train, both operating systems are able to boot successfully.

Change-Id: Iff788b2ff17ba190a8dd9b0b540f1ef059a1a0ea
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/43380
Reviewed-by: Patrick Rudolph <siro@das-labor.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

0 files changed, 0 insertions, 0 deletions