No support for RVV/SVE need to use SVE

[hmacdope]

Issue with MacOS is to do with the following from the highway doc (basically won't compile for SVE)

On RVV/SVE, vectors are sizeless and cannot be wrapped inside a class. The
Highway API allows using built-in types as vectors because operations are
expressed as overloaded functions. Instead of constructors, overloaded
initialization functions such as `Set` take a zero-sized tag argument called `d`
of type `D` and return an actual vector of unspecified type.

Originally posted by @hmacdope in #185 (comment)