MAX17201/MAX17205 Fuel Gauge
----------------------------

Required properties :
 - compatible : "maxim,max1720x"

Optional properties :
 - maxim,psy-type-unknown: if set, forces poser supply type to be
   POWER_SUPPLY_TYPE_UNKNOWN rather than POWER_SUPPLY_TYPE_BATTERY

 - io-channels: see Documentation/devicetree/bindings/iio/iio-bindings.txt
 - io-channel-names: see Documentation/devicetree/bindings/iio/iio-bindings.txt
 - maxim,batt-id-range-pct: tolerance in percent on the resitance ID value. if
   not provided, defaults to 20%.

 - maxim,config: node in which children would have a "maxim,batt-id-kohm"
   property and a "maxim,regval" to allow applying configuration changes given a
   battery.
 - maxim,batt-id-kohm: the value of the battery resitance ID the config applies
   to.
 - maxim,n_regval: An array of u16 that are pairs of register address and
   corresponding values. These values will be written to the shadow registers
   of Maxim fuel gauge their address must be within 0x80 - 0xDF to be considered
 - maxim,r_regval: An array of u16 that are pairs of register address and
   corresponding values. These values will be written to the ModelGauge m5
   Register their address must be within 0x00 - 0x4D, 0xB0 - 0xDF to be
   considered.