If you are renting an RV (including a travel trailer or motor home), the income from that rental is reported on Schedule C. That’s still the case even if it’s an RV that is permanently parked on your property, such as a trailer that you rent out on Airbnb in the backyard. It doesn’t go on Schedule E because it’s not considered “real property”.
Land is never depreciable, so there’s no deduction for the land value the RV sits on. However, you can depreciate the cost of the RV as an expense over 5 years.
If you are renting out just a parking space for someone to park their own RV, then that would go on Schedule E.