ARC: HSDK-4xD: add initial board support

Add initial HSDK-4xD board support.
The ARC HS4x/HS4xD Development Kit includes a multicore ARC HS4xD-based
chip that integrates a wide range of interfaces including Ethernet,
HDMI, WiFi, Bluetooth, USB, SDIO, I2C, SPI, UART, I2S, ADC, PWM and
GPIO, as well as a Think Silicon GPU.

Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
diff --git a/configs/hsdk_4xd_defconfig b/configs/hsdk_4xd_defconfig
new file mode 100644
index 0000000..ccce534
--- /dev/null
+++ b/configs/hsdk_4xd_defconfig
@@ -0,0 +1,67 @@
+CONFIG_ARC=y
+CONFIG_ISA_ARCV2=y
+CONFIG_TARGET_HSDK=y
+CONFIG_BOARD_HSDK_4XD=y
+CONFIG_SYS_TEXT_BASE=0x81000000
+CONFIG_DM_GPIO=y
+CONFIG_DEBUG_UART_BASE=0xf0005000
+CONFIG_DEBUG_UART_CLOCK=33333333
+CONFIG_SYS_CLK_FREQ=500000000
+CONFIG_DEBUG_UART=y
+CONFIG_USE_BOOTARGS=y
+CONFIG_BOOTARGS="console=ttyS0,115200n8"
+CONFIG_BOARD_EARLY_INIT_F=y
+CONFIG_BOARD_EARLY_INIT_R=y
+CONFIG_HUSH_PARSER=y
+CONFIG_SYS_PROMPT="hsdk-4xd# "
+CONFIG_CMD_ENV_FLAGS=y
+# CONFIG_CMD_FLASH is not set
+CONFIG_CMD_MMC=y
+CONFIG_CMD_SPI=y
+CONFIG_CMD_USB=y
+# CONFIG_CMD_SETEXPR is not set
+CONFIG_CMD_DHCP=y
+CONFIG_CMD_PING=y
+CONFIG_CMD_CACHE=y
+CONFIG_CMD_EXT2=y
+CONFIG_CMD_EXT4=y
+CONFIG_CMD_EXT4_WRITE=y
+CONFIG_CMD_FAT=y
+CONFIG_OF_CONTROL=y
+CONFIG_OF_EMBED=y
+CONFIG_DEFAULT_DEVICE_TREE="hsdk"
+CONFIG_ENV_IS_IN_FAT=y
+CONFIG_ENV_FAT_INTERFACE="mmc"
+CONFIG_ENV_FAT_DEVICE_AND_PART="0:1"
+CONFIG_SYS_RELOC_GD_ENV_ADDR=y
+CONFIG_NET_RANDOM_ETHADDR=y
+CONFIG_DM=y
+CONFIG_CLK_HSDK=y
+CONFIG_HSDK_CREG_GPIO=y
+CONFIG_MMC=y
+CONFIG_DM_MMC=y
+CONFIG_MMC_DW=y
+CONFIG_MMC_DW_SNPS=y
+CONFIG_MTD=y
+CONFIG_DM_SPI_FLASH=y
+CONFIG_SPI_FLASH_SST=y
+CONFIG_DM_ETH=y
+CONFIG_ETH_DESIGNWARE=y
+CONFIG_MII=y
+CONFIG_DM_RESET=y
+CONFIG_DM_SERIAL=y
+CONFIG_DEBUG_UART_SHIFT=2
+CONFIG_DEBUG_UART_ANNOUNCE=y
+CONFIG_SYS_NS16550=y
+CONFIG_SPI=y
+CONFIG_DM_SPI=y
+CONFIG_DESIGNWARE_SPI=y
+CONFIG_USB=y
+CONFIG_DM_USB=y
+CONFIG_USB_EHCI_HCD=y
+CONFIG_USB_EHCI_GENERIC=y
+CONFIG_USB_OHCI_HCD=y
+CONFIG_USB_OHCI_GENERIC=y
+CONFIG_USB_STORAGE=y
+CONFIG_USE_PRIVATE_LIBGCC=y
+CONFIG_PANIC_HANG=y