[8u] RFR (XS) 8259568: PPC64 builds broken after JDK-8221408 8u backport

[Aleksey Shipilev]

This is 8u-specific bug:
   https://bugs.openjdk.java.net/browse/JDK-8259568

Please read the details in the bug report.

Fix:
   http://cr.openjdk.java.net/~shade/8259568/webrev.01/

Testing: Linux PPC64 build (used to fail before, passes now); jcstress (running)

-- 
Thanks,
-Aleksey