ARC: HSDK: introduce CREG GPIO driver

The HSDK can manage some pins via CREG registers block.

Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 81f55a5..201d7bf 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -54,6 +54,7 @@
 obj-$(CONFIG_ZYNQ_GPIO)		+= zynq_gpio.o
 obj-$(CONFIG_VYBRID_GPIO)	+= vybrid_gpio.o
 obj-$(CONFIG_HIKEY_GPIO)	+= hi6220_gpio.o
+obj-$(CONFIG_HSDK_CREG_GPIO)	+= hsdk-creg-gpio.o
 obj-$(CONFIG_IMX_RGPIO2P)	+= imx_rgpio2p.o
 obj-$(CONFIG_PIC32_GPIO)	+= pic32_gpio.o
 obj-$(CONFIG_MVEBU_GPIO)	+= mvebu_gpio.o