增加Providor

wget https://cdn.jsdelivr.net/gh/openwrt/packages/net/ddns-scripts/files/usr/share/ddns/default/dnspod.cn.json -O /usr/share/ddns/default/dnspod.cn.json
wget https://cdn.jsdelivr.net/gh/openwrt/packages/net/ddns-scripts/files/usr/lib/ddns/update_dnspod_cn.sh -O /usr/lib/ddns/update_dnspod_cn.sh

在OpenWrt正常配置DDNS即可