FYI: 6784: Getting rid of compiler warnings in the agent

[Marcus Hirt]

What the title says.

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Commit messages:
 - 6784: Getting rid of compiler warnings in the agent

Changes: https://git.openjdk.java.net/jmc/pull/74/files
 Webrev: https://webrevs.openjdk.java.net/jmc/74/webrev.00
  Issue: https://bugs.openjdk.java.net/browse/JMC-6784
  Stats: 10 lines in 4 files changed: 9 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jmc/pull/74.diff
  Fetch: git fetch https://git.openjdk.java.net/jmc pull/74/head:pull/74

PR: https://git.openjdk.java.net/jmc/pull/74