Qualcomm Technologies,Inc. Adreno/Snapdragon hdmi display manager

Required properties:
- compatible: "qcom,hdmi-display"
- label: label of this display manager

Optional properties:
- qcom,display-type: display type of this manager. It could be "primary",
  "secondary", "tertiary", etc.
- qcom,non-pluggable: Indicate if display is non pluggable.
- qcom,display-panel: display panel node. It shares same syntax with DSI panel
  device tree.

Example:

/ {
	...

	hdmi_display: qcom,hdmi-display {
		compatible = "qcom,hdmi-display";
		label = "hdmi_display";
		qcom,display-type = "secondary";
		qcom,non-pluggable;
		qcom,display-panel = <&hdmi_customized_mode>;
	};

};