RFR: 8309111: Removing unused constructor of PerfLongCounter and PerfLongVariable

[Albert Mingkun Yang]

Trivial removing dead code.

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Commit messages:
 - perf-data-remove

Changes: https://git.openjdk.org/jdk/pull/14219/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=14219&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8309111
  Stats: 17 lines in 2 files changed: 0 ins; 17 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/14219.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/14219/head:pull/14219

PR: https://git.openjdk.org/jdk/pull/14219