RFR: 8374168: Resolve disabled warnings in JDWP agent

[Alex Menkov]

The fix resolves disabled warnings in debugger agent

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Commit messages:
 - fix

Changes: https://git.openjdk.org/jdk/pull/28937/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=28937&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8374168
  Stats: 54 lines in 10 files changed: 18 ins; 32 del; 4 mod
  Patch: https://git.openjdk.org/jdk/pull/28937.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/28937/head:pull/28937

PR: https://git.openjdk.org/jdk/pull/28937