RFR: 8374713: PredicatedConcurrentWriteOp is unused

[Francesco Andreuzzi]

Trivial removal of `PredicatedConcurrentWriteOp`, which is not used anymore after [8284161](https://bugs.openjdk.org/browse/JDK-8284161).

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

Commit messages:
 - nn

Changes: https://git.openjdk.org/jdk/pull/29088/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=29088&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8374713
  Stats: 12 lines in 1 file changed: 0 ins; 12 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/29088.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/29088/head:pull/29088

PR: https://git.openjdk.org/jdk/pull/29088