RFR: 8221639: [x32] expand_exec_shield_cs_limit workaround is undefined code after JDK-8199717

[Florian Weimer]

* Severin Gehwolf:

> Hi,
>
> Could I please get reviews for this Linux x32 fix? JDK-8199717 added a
> performance optimization to only capture the initial stack size when
> launched via non-java launchers. However, on Linux x32,

Do you mean actual x32, or i386?  These two are different.

Can you actually verify changes in this area?  I think it's pretty hard
these days to find a machine that actually uses the CS hack to avoid
universal read-implies-exec.  I don't think this was ever part of any
mainline kernel.

Thanks,
Florian