x86: Add a generic Intel GPIO driver

Add a GPIO driver which uses the pinctrl driver to access the pad
information. This driver relies on the GPIO nodes being subnodes to the
pinctrl device.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 3612e66..449046b 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -17,6 +17,7 @@
 obj-$(CONFIG_AT91_GPIO)	+= at91_gpio.o
 obj-$(CONFIG_ATMEL_PIO4)	+= atmel_pio4.o
 obj-$(CONFIG_BCM6345_GPIO)	+= bcm6345_gpio.o
+obj-$(CONFIG_INTEL_GPIO)	+= intel_gpio.o
 obj-$(CONFIG_INTEL_ICH6_GPIO)	+= intel_ich6_gpio.o
 obj-$(CONFIG_INTEL_BROADWELL_GPIO)	+= intel_broadwell_gpio.o
 obj-$(CONFIG_KIRKWOOD_GPIO)	+= kw_gpio.o