AST2700 SoCs integrates a Ibex 32-bits RISC-V core as the boot MCU
for the first stage bootloader execution, namely SPL.
This patch implements the preliminary base to successfully run SPL
on this RV32-based MCU to the console banner message.
Signed-off-by: Chia-Wei Wang <chiawei_wang@aspeedtech.com>
Reviewed-by: Leo Yu-Chi Liang <ycliang@andestech.com>