This is the initial implementation of Shakti UART.

Signed-off-by: Vijai Kumar K <vijai@behindbytes.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 20210401181457.73039-4-vijai@behindbytes.com
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>