RFR: 8286891: thread_local causes undefined symbol error with XL C [v2]

[Tyler Steele]

> When using XLClang++ to compile a `thread_local` struct with a destructor, a compiler bug is exposed that results in a missing constructor and a linker error.
> 
> Adding the missing constructor solves this issue.
> 
> Changes
> - Builds on AIX (previously broken)

Tyler Steele has updated the pull request incrementally with one additional commit since the last revision:

  Remove AIX-specific macro

-------------

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/8754/files
  - new: https://git.openjdk.java.net/jdk/pull/8754/files/06073958..5dd93583

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=8754&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=8754&range=00-01

  Stats: 3 lines in 1 file changed: 0 ins; 2 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk/pull/8754.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/8754/head:pull/8754

PR: https://git.openjdk.java.net/jdk/pull/8754