ARC: [plat-hsdk]: enable creg-gpio controller

HSDK SOC has CREG GPIO controller which can be used to control
SPI chip select lines.
Enable it in preparation of enabling SPI peripherals.
Acked-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

arch/arc/boot/dts/hsdk.dts

@@ -241,6 +241,14 @@ mmc@a000 {
 			dma-coherent;
 		};
 
+		creg_gpio: gpio@14b0 {
+			compatible = "snps,creg-gpio-hsdk";
+			reg = <0x14b0 0x4>;
+			gpio-controller;
+			#gpio-cells = <2>;
+			ngpios = <2>;
+		};
+
 		gpio: gpio@3000 {
 			compatible = "snps,dw-apb-gpio";
 			reg = <0x3000 0x20>;

arch/arc/configs/hsdk_defconfig

@@ -49,6 +49,7 @@ CONFIG_SERIAL_OF_PLATFORM=y
 CONFIG_GPIOLIB=y
 CONFIG_GPIO_SYSFS=y
 CONFIG_GPIO_DWAPB=y
+CONFIG_GPIO_SNPS_CREG=y
 # CONFIG_HWMON is not set
 CONFIG_DRM=y
 # CONFIG_DRM_FBDEV_EMULATION is not set