soc/amd/picasso/acpi: use ROOT_BRIDGE macro

Instead of having the different static parts of the PCI0 device in
northbridge.asl and sb_pci0_fch.asl, instantiate the static parts of the
PCI0 device via the ROOT_BRIDGE macro in soc.asl.

TEST=Both Ubuntu 2022.4 and Windows 10 still boot successfully and don't
show any new ACPI-related error.

Signed-off-by: Felix Held <felix-coreboot@felixheld.de>
Change-Id: I2587d8bb270dc3edce9dfa570a5018116fc9187f
Reviewed-on: https://review.coreboot.org/c/coreboot/+/75569
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Raul Rangel <rrangel@chromium.org>
diff --git a/src/soc/amd/picasso/acpi/soc.asl b/src/soc/amd/picasso/acpi/soc.asl
index f44f873..82c2766 100644
--- a/src/soc/amd/picasso/acpi/soc.asl
+++ b/src/soc/amd/picasso/acpi/soc.asl
@@ -1,6 +1,10 @@
 /* SPDX-License-Identifier: GPL-2.0-only */
 
-Device(PCI0) {
+#include <soc/amd/common/acpi/pci_root.asl>
+
+ROOT_BRIDGE(PCI0)
+
+Scope(PCI0) {
 	/* Describe the AMD Northbridge */
 	#include "northbridge.asl"