hw/intc/loongarch_extioi: Get cpu number from possible_cpu_arch_ids

Supported CPU number can be acquired from function
possible_cpu_arch_ids(), cpu-num property is not necessary.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Reviewed-by: Bibo Mao <maobibo@loongson.cn>
3 files changed