msm: mhi_uci: Add support for platform devices

MSM MHI UCI interface device

MHI userpace control interface (UCI) enables userspace software clients to

communicate with device using MHI protocol.

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Node Structure

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Main node properties:

- compatible

  Usage: required

  Value type: <string>

  Definition: "qcom,mhi-uci"

- qcom,mhi-uci-channels

  Usage: required

  Value type: Array of <u32>

  Definition: Array tuples which define the channel configuration

	parameters.  Each tuple is of length 2, 1st value

	represent channel, and 2nd value represent maximum

	payload supported.  Maximum payload supported is 64

	bytes.  Number of tuples must be even value.  Max # of

	tuples is 46.

- qcom,mhi-uci-ctrlchan

  Usage: optional

  Value type: <u32>

  Definition: Channel that will be handling flow control (DTR/RTS) signals.

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Example

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qcom,mhi-uci@0 {

	compatible = "qcom,mhi-uci";

	qcom,mhi-uci-channels = <0 0x1000>,

				<1 0x1000>,

				<2 0x1000>,

				<3 0xffff>,

				<10 0x1000>,

				<11 0x1000>,

				<14 0x1000>,

				<15 0x1000>,

				<16 0x1000>,

				<17 0x1000>,

				<18 0x1000>,

				<19 0x1000>,

				<24 0x1000>,

				<25 0x1000>,

				<32 0x1000>,

				<33 0x1000>;

	qcom,mhi-uci-ctrlchan = <18>;

	status = "ok";

};