[v4 PATCH 1/2] [PowerPC] Add simd.h implementation

[Shawn Landden]

On Wed, May 15, 2019 at 1:27 AM Christophe Leroy
<christophe.leroy at c-s.fr> wrote:
> Could you please as usual list here the changes provided by each version
> to ease the review ?
A bunch of embarrassing stuff that caused it not to build on some
set-ups (the functions were under the wrong include guards), and I
added include guards on simd.h so that you can use may_use_simd() even
if you don't have the FPU enabled (ARM's simd.h does this).