nvdimm acpi: initialize the resource used by NVDIMM ACPI

32 bits IO port starting from 0x0a18 in guest is reserved for NVDIMM
ACPI emulation. The table, NVDIMM_DSM_MEM_FILE, will be patched into
NVDIMM ACPI binary code

OSPM uses this port to tell QEMU the final address of the DSM memory
and notify QEMU to emulate the DSM method

Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
