extcon: axp288: Add axp288 extcon driver support

This patch adds the extcon support for AXP288 PMIC which
has the BC1.2 charger detection capability. Additionally
it also adds the USB mux switching support b/w SOC and PMIC
based on GPIO control.

Signed-off-by: Ramakrishna Pallala <ramakrishna.pallala@intel.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
[cw00.choi: Modify the log message to keep the consistent log message pattern]
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
diff --git a/drivers/extcon/Makefile b/drivers/extcon/Makefile
index 9204114..ba787d0 100644
--- a/drivers/extcon/Makefile
+++ b/drivers/extcon/Makefile
@@ -5,6 +5,7 @@
 obj-$(CONFIG_EXTCON)		+= extcon.o
 obj-$(CONFIG_EXTCON_ADC_JACK)	+= extcon-adc-jack.o
 obj-$(CONFIG_EXTCON_ARIZONA)	+= extcon-arizona.o
+obj-$(CONFIG_EXTCON_AXP288)	+= extcon-axp288.o
 obj-$(CONFIG_EXTCON_GPIO)	+= extcon-gpio.o
 obj-$(CONFIG_EXTCON_MAX14577)	+= extcon-max14577.o
 obj-$(CONFIG_EXTCON_MAX77693)	+= extcon-max77693.o