forked from Mirrors/opensbi

The original code does not prevent the following scenarios: > sbi_ecall_register_extension(ext1); /* extension id (70-80) */ > sbi_ecall_register_extension(ext2); /* extension id (50-100) */ Signed-off-by: Xiang Wang <merle@hardenedlinux.org> Reviewed-by: Anup Patel <anup.patel@wdc.com>