So just for clarification, are you looking for a drow deity who is keen on redeeming them (like Eilistraee) or just any Greyhawk deity who would encourage drow to turn good and worship them?
If the former, I'm unaware of any Greyhawk drow god who wants to "return their people to the light". I'd just port over Eilistraee.
If the latter, I can think of a couple of precedents.
In the City of Greyhawk boxed set there's an adventure revolving around a cleric of Pholtus who has converted a bunch of ogres to become "good". It's been ages since I read it, but I think they had only managed to become Neutral and backslided into violence after being attacked by mistrusting humans. Oh, and they kept on singing "Oh Blinding Light…".
Also, in Gary Gygax's Gord the Rogue series of novels there's a good-aligned drow priestess (she's a clone of Eclavdra and Gord's girlfriend - they're that kind of books). She gets her spells normally, so presumably she must be acceptable to whatever god she worships. Unfortunately I don't recall who that god was, or maybe Gygax never mentioned it.