成员的完整列表，这些成员属于 NIMQChatChannelSubscribeParam,包括所有继承而来的类成员

cb	NIMQChatChannelSubscribeParam
id_infos	NIMQChatChannelSubscribeParam
id_infos_count	NIMQChatChannelSubscribeParam
ope_type	NIMQChatChannelSubscribeParam
sub_type	NIMQChatChannelSubscribeParam
user_data	NIMQChatChannelSubscribeParam