hg: jdk9/hs/hotspot: 8176442: [aix] assert(_thr_current == 0L) failed: Thread::current already initialized

[david.holmes at oracle.com]

Changeset: a06c552214ed
Author:    stuefe
Date:      2017-03-13 21:46 -0400
URL:       http://hg.openjdk.java.net/jdk9/hs/hotspot/rev/a06c552214ed

8176442: [aix] assert(_thr_current == 0L) failed: Thread::current already initialized
Summary: Revert Thread::current() back to pthread library based TLS on AIX.
Reviewed-by: dholmes

! src/share/vm/utilities/globalDefinitions_xlc.hpp