RFR: 8327990: [macosx-aarch64] JFR enters VM without WXWrite [v2]

[Richard Reingruber]

> This pr changes  `JfrJvmtiAgent::retransform_classes()` and `jfr_set_enabled` to switch to `WXWrite` before transitioning to the vm.
> 
> Testing:
> make test TEST=jdk/jfr/event/runtime/TestClassLoadEvent.java TEST_VM_OPTS=-XX:+AssertWXAtThreadSync
> make test TEST=compiler/intrinsics/klass/CastNullCheckDroppingsTest.java TEST_VM_OPTS=-XX:+AssertWXAtThreadSync
> 
> More tests are pending.

Richard Reingruber has updated the pull request incrementally with one additional commit since the last revision:

  Set WXWrite at more locations

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/18238/files
  - new: https://git.openjdk.org/jdk/pull/18238/files/b34ad5f3..9075f4be

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=18238&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=18238&range=00-01

  Stats: 6 lines in 4 files changed: 5 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/18238.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/18238/head:pull/18238

PR: https://git.openjdk.org/jdk/pull/18238