hw/loongarch/virt: Remove unnecessay pre-boot setting with BSP

With BSP core, it boots from aux boot code and loads data into register
A0-A2 and PC. Pre-boot setting is not unnecessary and can be removed.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Reviewed-by: Song Gao <gaosong@loongson.cn>
Message-ID: <20250906070200.3749326-3-maobibo@loongson.cn>
Signed-off-by: Song Gao <gaosong@loongson.cn>
2 files changed