ARC: [plat-hsdk] Enable DW APB GPIO support

Enable GPIO support on HSDK. HSDK SoC includes Synopsys
DesignWare DW_apb_gpio IP with 24 GPIOs mapped onto port A.
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Acked-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

arch/arc/boot/dts/hsdk.dts

@@ -222,6 +222,21 @@ mmc@a000 {
 			bus-width = <4>;
 			dma-coherent;
 		};
+
+		gpio: gpio@3000 {
+			compatible = "snps,dw-apb-gpio";
+			reg = <0x3000 0x20>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			gpio_port_a: gpio-controller@0 {
+				compatible = "snps,dw-apb-gpio-port";
+				gpio-controller;
+				#gpio-cells = <2>;
+				snps,nr-gpios = <24>;
+				reg = <0>;
+			};
+		};
 	};
 
 	memory@80000000 {

arch/arc/configs/hsdk_defconfig

@@ -45,6 +45,9 @@ CONFIG_SERIAL_8250_CONSOLE=y
 CONFIG_SERIAL_8250_DW=y
 CONFIG_SERIAL_OF_PLATFORM=y
 # CONFIG_HW_RANDOM is not set
+CONFIG_GPIOLIB=y
+CONFIG_GPIO_SYSFS=y
+CONFIG_GPIO_DWAPB=y
 # CONFIG_HWMON is not set
 CONFIG_DRM=y
 # CONFIG_DRM_FBDEV_EMULATION is not set