Qualcomm Technologies, Inc. IPC Router MHI Transport

Required properties:
-compatible:		should be "qcom,ipc_router_mhi_xprt".
-qcom,mhi:		phandle of MHI Device to connect to.
-qcom,out-chan-id:	MHI Channel ID for the transmit path.
-qcom,in-chan-id:	MHI Channel ID for the receive path.
-qcom,xprt-remote:	string that defines the edge of the transport(PIL Name).
-qcom,xprt-linkid:	unique integer to identify the tier to which the link
			belongs to in the network and is used to avoid the
			routing loops while forwarding the broadcast messages.
-qcom,xprt-version:	unique version ID used by MHI transport header.

Example:
	qcom,ipc_router_external_modem_xprt2 {
		compatible = "qcom,ipc_router_mhi_xprt";
		qcom,mhi = <&mhi_wlan>;
	        qcom,out-chan-id = <34>;
		qcom,in-chan-id = <35>;
		qcom,xprt-remote = "external-modem";
		qcom,xprt-linkid = <1>;
		qcom,xprt-version = <3>;
	};
