QTI PMIC Glink binding

This binding describes the Qualcomm Technologies, Inc. PMIC GLink device. PMIC
Glink handles the communication between different clients (e.g. battery charger,
UCSI PPM) on the Application processor and charger firmware running on the
remote subsystem (e.g. DSP) over Glink channel.

- compatible:
	Usage: required
	Value type: <stringlist>
	Definition: must be "qcom,pmic-glink"

- qcom,pmic-glink-channel:
	Usage: required
	Value type: <stringlist>
	Definition: should be same as Glink channel name under rpmsg device.

- qcom,subsys-name:
	Usage: optional
	Value type: <stringlist>
	Definition: should be the subsystem name for which subsystem restart
		    notifications should be handled and state transitions be
		    sent to the clients.

- qcom,protection-domain:
	Usage: optional
	Value type: <stringlist>
	Definition: should be the protection domain service name and path name
		    for which notifications should be handled and state
		    transitions be sent to the clients.

Refer to Documentation/devicetree/bindings/soc/qcom/qcom,glink.txt for
information on rpmsg device ("qcom,pmic_glink_rpmsg" used in the example below)
that needs to be specified under a glink device.

= SUBNODE

Each subnode specifies a client of PMIC Glink device that will be instantiated
after the PMIC Glink device initializes.

= EXAMPLE

= PMIC Glink rpmsg device

&glink_adsp {
	...
	qcom,pmic_glink_rpmsg {
		qcom,glink-channels = "PMIC_RTR_ADSP_APPS";
	};
	...
};

= PMIC Glink device with child subnodes

&soc {
	qcom,pmic_glink {
		compatible = "qcom,pmic-glink";
		qcom,pmic-glink-channel = "PMIC_RTR_ADSP_APPS";
		qcom,subsys-name = "adsp";
		qcom,protection-domain = "tms/servreg", "msm/adsp/charger_pd";

		qcom,batt_chg {
			compatible = "qcom,battery-charger";
		};

		qcom,ucsi_ppm {
			compatible = "qcom,ucsi-ppm";
		};
	};
};