Presumably only for their own and Chinese brands however as I can't see anyone letting them do fabication for major players outside of China. They've also got a huge hurdle given they cant buy the standard equipment every chip fab needs owing to it all being produced by a single company.
If there's one company that has the capability to become a Samsung/Intel (IDM) on steroids, it is Huawei.
They have the money,talent, determination and state backing.