RFR(s) 8170873: PPC64: Poor StrictMath performance due to non-optimized compilation

[Roland Westrelin]

> I'll wait a review for PPC64. However I'm a little bit confused since the
> webrev I provide will, when applied to 8u, add aarch64 as well which is not
> currently in the 8u forest (maybe who pushes it could trim it off or use the
> previous webrev)...
>
> ... and maybe Andrew's reply (since he just added the aarch64-port-dev ML) was
> just for aarch64-port folks and I got it wrong... (it seems the case...)

I suppose it doesn't make much sense to include aarch64 in the non
aarch64 8u. Thanks anyway!

FYI, the commit message for the backport shouldn't use the backport's
bug id but the one from jdk 9 (8170153 in this case).

Roland.