power_supply: Add voltage_ocv property and use it for max17042 driver

This adds a new sysfs file called 'voltage_ocv' which gives the
Open Circuit Voltage of the battery.

This property can be used for platform shutdown policies and
can be useful for initial capacity estimations.

Note: This patch is generated against linux-next branch.

Signed-off-by: Ramakrishna Pallala <ramakrishna.pallala@intel.com>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
diff --git a/Documentation/power/power_supply_class.txt b/Documentation/power/power_supply_class.txt
index 9f16c51..211831d 100644
--- a/Documentation/power/power_supply_class.txt
+++ b/Documentation/power/power_supply_class.txt
@@ -84,6 +84,8 @@
 HEALTH - represents health of the battery, values corresponds to
 POWER_SUPPLY_HEALTH_*, defined in battery.h.
 
+VOLTAGE_OCV - open circuit voltage of the battery.
+
 VOLTAGE_MAX_DESIGN, VOLTAGE_MIN_DESIGN - design values for maximal and
 minimal power supply voltages. Maximal/minimal means values of voltages
 when battery considered "full"/"empty" at normal conditions. Yes, there is