gpio: lp873x: Add support for General Purpose Outputs

Add driver for lp873x PMIC family GPOs. Two GPOs are supported
and can be configured in Open-drain output or Push-pull output.

Signed-off-by: Keerthy <j-keerthy@ti.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 2a035ed..d60432f 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -56,6 +56,7 @@
 obj-$(CONFIG_GPIO_LP3943)	+= gpio-lp3943.o
 obj-$(CONFIG_GPIO_LPC18XX)	+= gpio-lpc18xx.o
 obj-$(CONFIG_ARCH_LPC32XX)	+= gpio-lpc32xx.o
+obj-$(CONFIG_GPIO_LP873X)	+= gpio-lp873x.o
 obj-$(CONFIG_GPIO_LYNXPOINT)	+= gpio-lynxpoint.o
 obj-$(CONFIG_GPIO_MAX730X)	+= gpio-max730x.o
 obj-$(CONFIG_GPIO_MAX7300)	+= gpio-max7300.o