[jdk17u-dev] RFR: 8294160: misc crash dump improvements

[Goetz Lindenmaier]

I backport this for parity with 17.0.7-oracle.

Omitting an edit in signals_posix.cpp which is in
code added by "8284161: Implementation of Virtual Threads (Preview)"

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Commit messages:
 - Backport 6f8f28e7566701b195ecc855f3e802cd7145e9aa

Changes: https://git.openjdk.org/jdk17u-dev/pull/1107/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=1107&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8294160
  Stats: 23 lines in 4 files changed: 20 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/1107.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev pull/1107/head:pull/1107

PR: https://git.openjdk.org/jdk17u-dev/pull/1107