mb/ocp/tiogapass/devicetree.cb: Add P2SB device

This fixes ocp/tiagopass not booting as after FSP-S the P2SB is
accessed to read out or reconfigure the HPET and PCH IOAPIC BDF.

Change-Id: Ia37bd0f14627980345cd07f20e935a10d4760b69
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/48654
Reviewed-by: Marc Jones <marc@marcjonesconsulting.com>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
diff --git a/src/mainboard/ocp/tiogapass/devicetree.cb b/src/mainboard/ocp/tiogapass/devicetree.cb
index 008633b..488f677 100644
--- a/src/mainboard/ocp/tiogapass/devicetree.cb
+++ b/src/mainboard/ocp/tiogapass/devicetree.cb
@@ -77,6 +77,7 @@
 				register "bmc_boot_timeout" = "90"
 			end
 		end # Intel Corporation C621 Series Chipset LPC/eSPI Controller
+		device pci 1f.1 hidden end # p2sb
 		device pci 1f.2 on end # Intel Corporation C620 Series Chipset Family Power Management Controller
 		device pci 1f.4 on end # Intel Corporation C620 Series Chipset Family SMBus
 		device pci 1f.5 on end # Intel Corporation C620 Series Chipset Family SPI Controller