Add support for virtual UART device that uses ARC Hostlink channels
for data transfers. Due to the Hostlink principle, this driver
supports only polling API.
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Evgeniy Paltsev <PaltsevEvgeniy@gmail.com>
