The default PCI mmcfg base is stored in ACPI MCFG table, when
CONFIG_ACPI_PARSE_ENABLED is set, acpi_fixup() function will
parse and fix up the platform mmcfg base in ACRN boot stage;
when it is not set, platform mmcfg base will be initialized to
DEFAULT_PCI_MMCFG_BASE which generated by acrn-config tool;
Please note we will not support platform which has multiple PCI
segment groups.
Tracked-On: #4157
Signed-off-by: Victor Sun <victor.sun@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>