If you override Equatable, you should also override other protocols that refine it, including Hashable. Your sample code violates the Hashable requirement (if a == b, then a.hashValue == b.hashValue), so types that use those implementations such as Set would have unexpected behaviors.
It's somewhat obscure here because Swift enum conforms to Equatable and Hashable by default.
Being deprecated only means you shouldn't use it. You should still implement it (correctly), so you should correct both hashInto and hashValue. That said, if you override either of those, the default implementation of the other will pick up your override (not sure how), so you'd be fine either way.
EDIT:
ok, I think you mean the deprecation warning about implementing hashValue itself. Yeah, in that case, you should just override hashInto.