[PATCH] Vectorise special cases for SVE inverse hyperbolics

[Paul Zimmermann]

       Hi Thomas,

> atanh -> 215% speed-up (5.51 ns/element to 1.75 ns/element)
> acosh -> 152% speed-up (4.63 ns/element to 1.84 ns/element)
> asinh ->  51% speed-up (5.00 ns/element to 3.31 ns/element)
> 
> Note that the numbers here are for the special case path only and that
> the fast path performance has been maintained.

how about accuracy? Is it unchanged?

Paul