RFR: 8349178: runtime/jni/atExit/TestAtExit.java should be supported on static JDK

[Jiangli Zhou]

Please review runtime/jni/atExit/TestAtExit.java test change:

- Remove `BUILD_HOTSPOT_JTREG_LIBRARIES_JDK_LIBS_libatExit := java.base:libjvm`. Don't explicitly link with libjvm, because it adds libjvm.so as a recorded dependency to libatExit.so (on Linux for example). That requires libjvm.so must be resolved and loaded successfully when libatExit.so is loaded. The static JDK (e.g. static-jdk image) does not provide a libjvm.so for runtime usage.
- Instead of calling the following functions directly in libatExit.c, change to look up the functions and calls them using the retrieved function addresses:
  - JNI_GetDefaultJavaVMInitArgs
  - JNI_GetCreatedJavaVMs
  - JNI_CreateJavaVM

On Linux (and similar) platform, there is no need to call `dlopen` for libjvm in libatExit.c explicitly, because the VM must already be loaded by the time when the libatExit native code is executed. Using `RTLD_DEFAULT` can "find symbols in the executable and its dependencies, as well as symbols in shared objects that were dynamically loaded with the RTLD_GLOBAL flag" (see https://man7.org/linux/man-pages/man3/dlsym.3.html).  https://github.com/openjdk/jdk/blob/9b49597244f898400222cfc252f50a2401ca3e2f/src/java.base/unix/native/libjli/java_md.c#L533 is where we `dlopen` libjvm with `RTLD_GLOBAL` for unix platform.

For Windows platform, I added Windows specific code to get the loaded `jvm.dll` first. If it can't find loaded `jvm.dll`, it then get the handle of the executable running the current process. The returned handle is used for finding the function addresses. 

TestAtExit passes with https://github.com/jianglizhou/jdk/actions/runs/13124407248/job/36619759000. TestAtExit also pass on static-jdk with my local jtreg run.

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Commit messages:
 - Fix typo.
 - - Remove BUILD_HOTSPOT_JTREG_LIBRARIES_JDK_LIBS_libatExit and don't link with libjvm for libatExit.

Changes: https://git.openjdk.org/jdk/pull/23431/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=23431&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8349178
  Stats: 56 lines in 2 files changed: 52 ins; 1 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/23431.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23431/head:pull/23431

PR: https://git.openjdk.org/jdk/pull/23431