RFR: 8357800: Initialize JvmtiThreadState bool fields with bool literals

[Aleksey Shipilev]

[JDK-8356251](https://bugs.openjdk.org/browse/JDK-8356251) changed `JvmtiThreadState._saved_interp_only_mode` from `int` to `bool`, which is good. But the initializations are still done with `0` literals. Even though it is benign, SonarCloud still complains about the intentionality of this initialization.

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Commit messages:
 - Fix

Changes: https://git.openjdk.org/jdk/pull/25458/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=25458&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8357800
  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/25458.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/25458/head:pull/25458

PR: https://git.openjdk.org/jdk/pull/25458