Add property memory region which can connect with IOMMU region to support SMMU translate.

Signed-off-by: Jianxian Wen <jianxian.wen@verisilicon.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 4C23C17B8E87E74E906A25A3254A03F4FA1FEC31@SHASXM03.verisilicon.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>