dt-bindings: power: supply: Extend max17040 compatibility

Maxim max17040 is a fuel gauge from a larger family utilising the Model
Gauge technology. Document all different compatible strings that the
max17040 driver recognizes.

Some devices in the wild report double the capacity. The
maxim,double-soc (from State-Of-Charge) property fixes that.
Examples: https://lore.kernel.org/patchwork/patch/1263411/#1468420

Signed-off-by: Iskren Chernev <iskren.chernev@gmail.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

Documentation/devicetree/bindings/power/supply/max17040_battery.txt

@@ -2,7 +2,9 @@ max17040_battery
 ~~~~~~~~~~~~~~~~
 
 Required properties :
- - compatible : "maxim,max17040" or "maxim,max77836-battery"
+ - compatible : "maxim,max17040", "maxim,max17041", "maxim,max17043",
+		"maxim,max17044", "maxim,max17048", "maxim,max17049",
+		"maxim,max17058", "maxim,max17059" or "maxim,max77836-battery"
  - reg: i2c slave address
 
 Optional properties :
@@ -11,6 +13,10 @@ Optional properties :
 				generated. Can be configured from 1 up to 32
 				(%). If skipped the power up default value of
 				4 (%) will be used.
+- maxim,double-soc : 		Certain devices return double the capacity.
+				Specify this boolean property to divide the
+				reported value in 2 and thus normalize it.
+				SOC == State of Charge == Capacity.
 - interrupts : 			Interrupt line see Documentation/devicetree/
 				bindings/interrupt-controller/interrupts.txt
 - wakeup-source :		This device has wakeup capabilities. Use this
@@ -31,3 +37,10 @@ Example:
 		interrupts = <2 IRQ_TYPE_EDGE_FALLING>;
 		wakeup-source;
 	};
+
+	battery-fuel-gauge@36 {
+		compatible = "maxim,max17048";
+		reg = <0x36>;
+		maxim,alert-low-soc-level = <10>;
+		maxim,double-soc;
+	};