power_supply: Add gpio charger driver

This patch adds a simple driver for chargers indicating their online
status through a GPIO pin.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
diff --git a/drivers/power/Makefile b/drivers/power/Makefile
index c75772e..545459f 100644
--- a/drivers/power/Makefile
+++ b/drivers/power/Makefile
@@ -32,3 +32,4 @@
 obj-$(CONFIG_BATTERY_INTEL_MID)	+= intel_mid_battery.o
 obj-$(CONFIG_CHARGER_ISP1704)	+= isp1704_charger.o
 obj-$(CONFIG_CHARGER_TWL4030)	+= twl4030_charger.o
+obj-$(CONFIG_CHARGER_GPIO)	+= gpio-charger.o