mb/google/nissa: Skip sending the MBP HOB to save boot time

This change is to skip sending the MBP HOB since coreboot doesn't
use it and also helps to reduce the boot time by ~40msec on ADL-N
variants.

Boot time data:
Before:
* 955:returning from FspSiliconInit    1,231,364 (117,051)
After:
* 955:returning from FspSiliconInit    1,198,221 (79,497)

BUG=b:241850107
TEST=Verified that boot time is reduced by ~40msec and also S0i3
is working.

Signed-off-by: V Sowmya <v.sowmya@intel.com>
Change-Id: Iaeaa8bcdf8467fdd467a10a98dd7582e8e0b067c
Reviewed-on: https://review.coreboot.org/c/coreboot/+/66442
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Reka Norman <rekanorman@chromium.org>
Reviewed-by: Kangheui Won <khwon@chromium.org>
Reviewed-by: Eric Lai <eric_lai@quanta.corp-partner.google.com>
diff --git a/src/mainboard/google/brya/variants/baseboard/nissa/devicetree.cb b/src/mainboard/google/brya/variants/baseboard/nissa/devicetree.cb
index 6cc2cb0..f0aacb3 100644
--- a/src/mainboard/google/brya/variants/baseboard/nissa/devicetree.cb
+++ b/src/mainboard/google/brya/variants/baseboard/nissa/devicetree.cb
@@ -85,6 +85,8 @@
 	# Disable Package C-state demotion for nissa baseboard.
 	register "disable_package_c_state_demotion" = "1"
 
+	register "skip_mbp_hob" = "1"
+
 	# Intel Common SoC Config
 	#+-------------------+---------------------------+
 	#| Field             |  Value                    |