RFR: 8371590: runtime/ErrorHandling/TestDwarf.java fails with clang toolchain

[Paul Hübner]

Hi all,

This fixes `runtime/ErrorHandling/TestDwarf.java` failing on Linux+Clang. Two sub-tests are patched.

#### `crashNativeMultipleMethods`

Disallow inlining of `foo` to ensure it appears in the native frames stack, where it can be picked up by the test process analyser. 

#### `crashNativeDereferenceNull` 

Preventatively also disable inlining for `dereference_null` since it's searched for in the stack. With Clang, the JVM process can exit without an hs_err file, so skip the subtest. `crashNativeMultipleMethods` already checks the stack frames, so we are not losing coverage. Furthermore, the vast majority of the world uses a GCC-built JDK anyway.

Testing: Ran the test for 20 iterations on Linux+GCC and Linux+Clang without failure. Also tier1 on Linux, macOS and Windows as a sanity test.

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

Commit messages:
 - Fix failing test.

Changes: https://git.openjdk.org/jdk/pull/29451/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=29451&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8371590
  Stats: 24 lines in 3 files changed: 16 ins; 0 del; 8 mod
  Patch: https://git.openjdk.org/jdk/pull/29451.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/29451/head:pull/29451

PR: https://git.openjdk.org/jdk/pull/29451