[lilliput-jdk17u:lilliput] RFR: 8300566: [Lilliput/JDK17] Properly set ZF on anon-check path

[Roman Kennke]

In AArch64's fast_unlock(), we need to check if the monitor owner is ANONYMOUS (only with Lilliput/fast-locking), and if so, call the runtime to fix this before exiting the monitor. I tried to be smart and used tbnz there, but it turns out that tbnz does *not* set the zero flag, but we do need the ZF set correctly on exit of fast_unlock, so that C2 generated code would actually call the slow path. Therefore we need to use the longer tst/br instructions instead.

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Commit messages:
 - 8300566: [Lilliput/JDK17] Properly set ZF on anon-check path

Changes: https://git.openjdk.org/lilliput-jdk17u/pull/4/files
 Webrev: https://webrevs.openjdk.org/?repo=lilliput-jdk17u&pr=4&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8300566
  Stats: 5 lines in 1 file changed: 4 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/lilliput-jdk17u/pull/4.diff
  Fetch: git fetch https://git.openjdk.org/lilliput-jdk17u pull/4/head:pull/4

PR: https://git.openjdk.org/lilliput-jdk17u/pull/4