REF:https://bugzilla.tianocore.org/show_bug.cgi?id=1496 Several updates have been made to the OvmfPkg/AcpiPlatformDxe driver to drop its dependency on PcAtChipsetPkg: A) Consumes the PCD 'Pcd8259LegacyModeEdgeLevel' defined within OvmfPkg; B) Remove the PcAtChipsetPkg DEC file dependency in the driver INF file. Cc: Jordan Justen <jordan.l.justen@intel.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Ray Ni <ray.ni@intel.com> Signed-off-by: Hao Wu <hao.a.wu@intel.com> Reviewed-by: Laszlo Ersek <lersek@redhat.com>