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>
6 files changed