ASoC: qcom: dt-bindings: Add sdm845 machine bindings

* Qualcomm Technologies Inc. SDM845 ASoC sound card driver

This binding describes the SDM845 sound card, which uses qdsp for audio.

- compatible:

	Usage: required

	Value type: <stringlist>

	Definition: must be "qcom,sdm845-sndcard"

- audio-routing:

	Usage: Optional

	Value type: <stringlist>

	Definition:  A list of the connections between audio components.

		  Each entry is a pair of strings, the first being the

		  connection's sink, the second being the connection's

		  source. Valid names could be power supplies, MicBias

		  of codec and the jacks on the board.

- model:

	Usage: required

	Value type: <stringlist>

	Definition: The user-visible name of this sound card.

= dailinks

Each subnode of sndcard represents either a dailink, and subnodes of each

dailinks would be cpu/codec/platform dais.

- link-name:

	Usage: required

	Value type: <string>

	Definition: User friendly name for dai link

= CPU, PLATFORM, CODEC dais subnodes

- cpu:

	Usage: required

	Value type: <subnode>

	Definition: cpu dai sub-node

- codec:

	Usage: required

	Value type: <subnode>

	Definition: codec dai sub-node

- platform:

	Usage: Optional

	Value type: <subnode>

	Definition: platform dai sub-node

- sound-dai:

	Usage: required

	Value type: <phandle>

	Definition: dai phandle/s and port of CPU/CODEC/PLATFORM node.

Example:

audio {

	compatible = "qcom,sdm845-sndcard";

	model = "sdm845-snd-card";

	pinctrl-names = "default", "sleep";

	pinctrl-0 = <&pri_mi2s_active &pri_mi2s_ws_active>;

	pinctrl-1 = <&pri_mi2s_sleep &pri_mi2s_ws_sleep>;

	mm1-dai-link {

		link-name = "MultiMedia1";

		cpu {

			sound-dai = <&q6asmdai MSM_FRONTEND_DAI_MULTIMEDIA1>;

		};

	};

	pri-mi2s-dai-link {

		link-name = "PRI MI2S Playback";

		cpu {

			sound-dai = <&q6afedai PRIMARY_MI2S_RX>;

		};

		platform {

			sound-dai = <&q6routing>;

		};

	};

};