RFR: 8281043: Intrinsify recursive ObjectMonitor locking for PPC64

[Martin Doerr]

PPC64 implementation of JDK-8277180.

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Commit messages:
 - 8281043: Intrinsify recursive ObjectMonitor locking for PPC64

Changes: https://git.openjdk.java.net/jdk/pull/7305/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=7305&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8281043
  Stats: 21 lines in 1 file changed: 8 ins; 3 del; 10 mod
  Patch: https://git.openjdk.java.net/jdk/pull/7305.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/7305/head:pull/7305

PR: https://git.openjdk.java.net/jdk/pull/7305