x86/acpi: Add VFCT table

Add VFCT table to provide PCI Optiom Rom for
AMD graphic devices.
Useful for GNU Linux payloads and embedded dual GPU systems.

Tested on Lenovo T500 with AMD RV635 as secondary gpu.

Original Change-Id: I3b4a587c71e7165338cad3aca77ed5afa085a63c
Signed-off-by: Patrick Rudolph <siro@das-labor.org>

Change-Id: I4dc00005270240c048272b2e4f52ae46ba1c9422
Reviewed-on: https://review.coreboot.org/18192
Tested-by: build bot (Jenkins)
Reviewed-by: Martin Roth <martinroth@google.com>
diff --git a/src/include/device/pci_rom.h b/src/include/device/pci_rom.h
index 2fb2f7a..3f09778 100644
--- a/src/include/device/pci_rom.h
+++ b/src/include/device/pci_rom.h
@@ -2,6 +2,7 @@
 #define PCI_ROM_H
 #include <endian.h>
 #include <stddef.h>
+#include <arch/acpi.h>
 
 #define PCI_ROM_HDR 0xAA55
 #define PCI_DATA_HDR (uint32_t) ( ('R' << 24) | ('I' << 16) | ('C' << 8) | 'P' )
@@ -35,6 +36,12 @@
 
 struct rom_header *pci_rom_probe(struct device *dev);
 struct rom_header *pci_rom_load(struct device *dev, struct rom_header *rom_header);
+
+unsigned long
+pci_rom_write_acpi_tables(struct device *device,
+						  unsigned long current,
+						  struct acpi_rsdp *rsdp);
+
 u32 map_oprom_vendev(u32 vendev);
 
 #endif