[Bug c/61727] #pragma simd is undocumented

[andi-gcc at firstfloor dot org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61727

--- Comment #4 from Andi Kleen <andi-gcc at firstfloor dot org> ---
This was originally about the #pragma simd in CIlk+, which has been removed.
But it lives on in #pragma omp simd