You do not need a seperate WPS for repairs under ASME. However, if your doing ASME you are probably being audited by ASME and therefore I would be surprised if the auditors did not require you to address the weld repair process in some manner in either your manuals, or a General specification, of some other form of documentation as suits you. And this documentation would refer to the WPS you intend to use.
The language will pertain to excavation, inspection, PWHT, etc., or other details which may be alloy specific.