The owner of a San Fernando Valley hot dog stand wants singer Leslie Uggams and her husband to stop using his company's name, alleging that they served inferior food at their stand in Woodland Hills. Kevin Lentz, owner of the original Wiener Factory on Ventura Boulevard in Sherman Oaks, said in his Superior Court civil suit that Uggams and husband, Graham Pratt, breached the 1984 agreement they signed when they licensed the Wiener Factory name to open a stand of their own. Customers go into the Woodland Hills restaurant "and get what they think is lousy food," said Lentz's attorney Scott Bernstein. "Then they come and complain to the owner, Mr. Lentz." Told of Lentz's charge, Les Hanig, co-owner of the Woodland Hills outlet, laughed and said: "I get the same complaints about his restaurant." Bernstein said Lentz's reputation is at stake because the original Wiener Factory, in business for more than 16 years, is "kind of a Valley landmark."