Revert "riscv: image: Add new image type for RV64"

This reverts commit 14a4792a71db3561bea065415ac1f2ac69ef32b5 as
discussed in [1].

[1] https://lists.denx.de/pipermail/u-boot/2025-May/590841.html

Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com>
Reviewed-by: Leo Yu-Chi Liang <ycliang@andestech.com>
2 files changed