[clang] [llvm] [AArch64] Implement NEON vscale intrinsics (PR #100347)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `llvm-clang-x86_64-sie-win` running on `sie-win-worker` while building `clang,llvm` at step 7 "test-build-unified-tree-check-all".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/46/builds/5582

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

```
Step 7 (test-build-unified-tree-check-all) failure: test (failure)
******************** TEST 'Clang :: CodeGen/aarch64-neon-fp8-intrinsics/acle_neon_fscale.c' FAILED ********************
Exit Code: 2

Command Output (stdout):
--
# RUN: at line 4
z:\b\llvm-clang-x86_64-sie-win\build\bin\clang.exe -cc1 -internal-isystem Z:\b\llvm-clang-x86_64-sie-win\build\lib\clang\20\include -nostdsysteminc -triple aarch64-none-linux-gnu -target-feature +neon -target-feature +fp8 -O3 -emit-llvm -o - Z:\b\llvm-clang-x86_64-sie-win\llvm-project\clang\test\CodeGen\aarch64-neon-fp8-intrinsics\acle_neon_fscale.c | z:\b\llvm-clang-x86_64-sie-win\build\bin\filecheck.exe Z:\b\llvm-clang-x86_64-sie-win\llvm-project\clang\test\CodeGen\aarch64-neon-fp8-intrinsics\acle_neon_fscale.c
# executed command: 'z:\b\llvm-clang-x86_64-sie-win\build\bin\clang.exe' -cc1 -internal-isystem 'Z:\b\llvm-clang-x86_64-sie-win\build\lib\clang\20\include' -nostdsysteminc -triple aarch64-none-linux-gnu -target-feature +neon -target-feature +fp8 -O3 -emit-llvm -o - 'Z:\b\llvm-clang-x86_64-sie-win\llvm-project\clang\test\CodeGen\aarch64-neon-fp8-intrinsics\acle_neon_fscale.c'
# .---command stderr------------
# | Z:\b\llvm-clang-x86_64-sie-win\llvm-project\clang\test\CodeGen\aarch64-neon-fp8-intrinsics\acle_neon_fscale.c:2:10: fatal error: 'arm_neon.h' file not found
# |     2 | #include <arm_neon.h>
# |       |          ^~~~~~~~~~~~
# | 1 error generated.
# `-----------------------------
# error: command failed with exit status: 1
# executed command: 'z:\b\llvm-clang-x86_64-sie-win\build\bin\filecheck.exe' 'Z:\b\llvm-clang-x86_64-sie-win\llvm-project\clang\test\CodeGen\aarch64-neon-fp8-intrinsics\acle_neon_fscale.c'
# .---command stderr------------
# | FileCheck error: '<stdin>' is empty.
# | FileCheck command line:  z:\b\llvm-clang-x86_64-sie-win\build\bin\filecheck.exe Z:\b\llvm-clang-x86_64-sie-win\llvm-project\clang\test\CodeGen\aarch64-neon-fp8-intrinsics\acle_neon_fscale.c
# `-----------------------------
# error: command failed with exit status: 2

--

********************


```

</details>

https://github.com/llvm/llvm-project/pull/100347