[clang] [llvm] [WebAssembly] Represent reference types as TargetExtType (PR #203165)

[LLVM Continuous Integration via cfe-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `clang-aarch64-sve2-vla` running on `linaro-g4-02` while building `clang,llvm` at step 7 "ninja check 1".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/198/builds/13892

<details>
<summary>Here is the relevant piece of the build log for the reference</summary>

```
Step 7 (ninja check 1) failure: 1200 seconds without output running [b'ninja', b'check-all'], attempting to kill
...
llvm-lit: /home/tcwg-buildbot/worker/clang-aarch64-sve2-vla/llvm/flang/test/lit.cfg.py:203: note: using flang implicit search paths: -fintrinsic-modules-path=/home/tcwg-buildbot/worker/clang-aarch64-sve2-vla/stage1/lib/clang/23/finclude/flang/aarch64-unknown-linux-gnu
llvm-lit: /home/tcwg-buildbot/worker/clang-aarch64-sve2-vla/llvm/flang/test/lit.cfg.py:206: note: using flang extra search paths: 
llvm-lit: /home/tcwg-buildbot/worker/clang-aarch64-sve2-vla/llvm/llvm/utils/lit/lit/llvm/config.py:569: note: using clang: /home/tcwg-buildbot/worker/clang-aarch64-sve2-vla/stage1/bin/clang
llvm-lit: /home/tcwg-buildbot/worker/clang-aarch64-sve2-vla/llvm/llvm/utils/lit/lit/discovery.py:273: warning: input '/home/tcwg-buildbot/worker/clang-aarch64-sve2-vla/stage1/runtimes/runtimes-bins/compiler-rt/test/interception/Unit' contained no tests
llvm-lit: /home/tcwg-buildbot/worker/clang-aarch64-sve2-vla/llvm/llvm/utils/lit/lit/discovery.py:273: warning: input '/home/tcwg-buildbot/worker/clang-aarch64-sve2-vla/stage1/runtimes/runtimes-bins/compiler-rt/test/sanitizer_common/Unit' contained no tests
llvm-lit: /home/tcwg-buildbot/worker/clang-aarch64-sve2-vla/llvm/llvm/utils/lit/lit/llvm/config.py:569: note: using ld.lld: /home/tcwg-buildbot/worker/clang-aarch64-sve2-vla/stage1/bin/ld.lld
llvm-lit: /home/tcwg-buildbot/worker/clang-aarch64-sve2-vla/llvm/llvm/utils/lit/lit/llvm/config.py:569: note: using lld-link: /home/tcwg-buildbot/worker/clang-aarch64-sve2-vla/stage1/bin/lld-link
llvm-lit: /home/tcwg-buildbot/worker/clang-aarch64-sve2-vla/llvm/llvm/utils/lit/lit/llvm/config.py:569: note: using ld64.lld: /home/tcwg-buildbot/worker/clang-aarch64-sve2-vla/stage1/bin/ld64.lld
llvm-lit: /home/tcwg-buildbot/worker/clang-aarch64-sve2-vla/llvm/llvm/utils/lit/lit/llvm/config.py:569: note: using wasm-ld: /home/tcwg-buildbot/worker/clang-aarch64-sve2-vla/stage1/bin/wasm-ld
-- Testing: 110824 tests, 48 workers --
command timed out: 1200 seconds without output running [b'ninja', b'check-all'], attempting to kill
process killed by signal 9
program finished with exit code -1
elapsedTime=1320.799783

```

</details>

https://github.com/llvm/llvm-project/pull/203165