gryoung, in our patio villa, those 4 wall switches control the front porch/lanai light, the coach lights outside (beside the garage door), the entrance ceiling light, and the ceiling fan in the lanai. If you don't have that ceiling fan, there is probably a cover plate in the lanai ceiling where they've pre-wired for hanging a fan. That's what the non-functional inside wall switch would be for.
Bill