RFR: 8286303: Serial: Remove reference to ParGCRareEvent_lock [v3]

[Thomas Schatzl]

> Hi all,
> 
>   can I have reviews for this removal of an unused reference of ParGCRareEvent_lock in serial gc code - it is the only user of this BOT code, the other collectors have their own, completely separate one as far as I can tell.
> 
> Testing: gha, tier1-5
> 
> Thanks,
> Thomas

Thomas Schatzl has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains three additional commits since the last revision:

 - Merge branch 'master' into 8286303-pargcrareeventlock-remove-serial
 - Initial implementation
 - initial changes

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/8576/files
  - new: https://git.openjdk.java.net/jdk/pull/8576/files/d195077b..a09c65b6

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=8576&range=02
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=8576&range=01-02

  Stats: 103469 lines in 1246 files changed: 93928 ins; 4531 del; 5010 mod
  Patch: https://git.openjdk.java.net/jdk/pull/8576.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/8576/head:pull/8576

PR: https://git.openjdk.java.net/jdk/pull/8576