Introduce the FW_CFG_IO_DMA_ADDRESS macro for IO Ports 0x514 and 0x518 (most significant and least significant halves of the DMA Address Register, respectively), and update all references in OvmfPkg. Cc: Jordan Justen <jordan.l.justen@intel.com> Suggested-by: Jordan Justen <jordan.l.justen@intel.com> Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>