power: qpnp-fg: add support for battery age estimation

- qcom,cycle-counter-high-soc:		High SOC threshold which will be compared

					against the battery SOC before incrementing

					the cycle counter.

- qcom,capacity-learning-on:		A boolean property to have the fuel

					gauge driver attempt to learn the

					battery capacity when charging. Takes

					precedence over capacity-estimation-on.

- qcom,cl-max-increment-deciperc:	The maximum percent that the capacity

					can rise as the result of a single

					charge cycle. This property corresponds

					to .1% increments.

- qcom,cl-max-decrement-deciperc:	The maximum percent that the capacity

					can fall as the result of a single

					charge cycle. This property corresponds

					to .1% decrements.

- qcom,cl-max-temp-decidegc:		Above this temperature, capacity

					learning will be canceled.

- qcom,cl-mix-temp-decidegc:		Below this temperature, capacity

					learning will be canceled.

- qcom,cl-max-start-soc:		The battery soc has to be below this

					value at the start of a charge cycle

					for capacity learning to be run.

- qcom,capacity-estimation-on:		A boolean property to have the fuel

					gauge driver attempt to estimate the

					battery capacity using battery

					resistance.

- qcom,aging-eval-current-ma:		Current used to evaluate battery aging.

					This value should be around the steady

					state current drawn from the battery

					when the phone is low on battery.

qcom,fg-soc node required properties:

- reg : offset and length of the PMIC peripheral register map.