RFR: 8344935: [ubsan]: javaThread.hpp:1241:52: runtime error: load of value 9831830, which is not a valid value for type 'freeze_result'

[Matthias Baesken]

Seems we miss initialization of  _last_freeze_fail_result in the  JavaThread constructor, this should be added.
Causes otherwise ubsan issues in the test  java/lang/Thread/virtual/MonitorEnterExit.java#Xcomp-TieredStopAtLevel1-LM_LEGACY 

/priv/jenkins/client-home/workspace/openjdk-jdk-weekly-linux_x86_64-opt/jdk/src/hotspot/share/runtime/javaThread.hpp:1241:52: runtime error: load of value 9831830, which is not a valid value for type 'freeze_result'
    #0 0x7f5edef378eb in JavaThread::last_freeze_fail_result() src/hotspot/share/runtime/javaThread.hpp:1241
    #1 0x7f5edef378eb in JVM_VirtualThreadPinnedEvent src/hotspot/share/prims/jvm.cpp:3805

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Commit messages:
 - JDK-8344935

Changes: https://git.openjdk.org/jdk/pull/22361/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=22361&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8344935
  Stats: 5 lines in 1 file changed: 4 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/22361.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/22361/head:pull/22361

PR: https://git.openjdk.org/jdk/pull/22361