[clang] [Win/X86] Make _m_prefetch[w] builtins to avoid winnt.h conflicts (PR #115099)

[LLVM Continuous Integration via cfe-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `openmp-offload-amdgpu-runtime` running on `omp-vega20-0` while building `clang` at step 5 "compile-openmp".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/30/builds/15169

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

```
Step 5 (compile-openmp) failure: build (failure)
...
1.162 [3618/32/702] Building DiagnosticIndexName.inc...
1.162 [3617/32/703] Building BuiltinsNVPTX.inc...
1.166 [3616/32/704] Building DiagnosticSemaEnums.inc...
1.167 [3615/32/705] Building BuiltinsX86_64.inc...
1.168 [3614/32/706] Building DiagnosticSerializationKinds.inc...
1.170 [3613/32/707] Building DiagnosticSerializationEnums.inc...
1.170 [3612/32/708] Building arm_fp16.inc...
1.175 [3611/32/709] Building DiagnosticGroups.inc...
1.177 [3610/32/710] Building BuiltinsHexagon.inc...
1.178 [3609/32/711] Building BuiltinsX86.inc...
FAILED: tools/clang/include/clang/Basic/BuiltinsX86.inc /home/ompworker/bbot/openmp-offload-amdgpu-runtime/llvm.build/tools/clang/include/clang/Basic/BuiltinsX86.inc 
cd /home/ompworker/bbot/openmp-offload-amdgpu-runtime/llvm.build && /home/ompworker/bbot/openmp-offload-amdgpu-runtime/llvm.build/bin/clang-tblgen -gen-clang-builtins -I /home/ompworker/bbot/openmp-offload-amdgpu-runtime/llvm.src/clang/include/clang/Basic -I/home/ompworker/bbot/openmp-offload-amdgpu-runtime/llvm.src/clang/include -I/home/ompworker/bbot/openmp-offload-amdgpu-runtime/llvm.build/tools/clang/include -I/home/ompworker/bbot/openmp-offload-amdgpu-runtime/llvm.build/include -I/home/ompworker/bbot/openmp-offload-amdgpu-runtime/llvm.src/llvm/include /home/ompworker/bbot/openmp-offload-amdgpu-runtime/llvm.src/clang/include/clang/Basic/BuiltinsX86.td --write-if-changed -o tools/clang/include/clang/Basic/BuiltinsX86.inc -d tools/clang/include/clang/Basic/BuiltinsX86.inc.d
/home/ompworker/bbot/openmp-offload-amdgpu-runtime/llvm.src/clang/include/clang/Basic/BuiltinsX86.td:147:7: error: Unexpected header name
  def _m_prefetch : X86LibBuiltin<"void(void *)">;
      ^
1.188 [3609/31/712] Building DiagnosticSemaKinds.inc...
1.193 [3609/30/713] Building arm_immcheck_types.inc...
1.204 [3609/29/714] Building arm_sve_typeflags.inc...
1.210 [3609/28/715] Building arm_mve_builtin_aliases.inc...
1.212 [3609/27/716] Building arm_neon.inc...
1.217 [3609/26/717] Building arm_mve_builtin_sema.inc...
1.218 [3609/25/718] Building arm_mve_builtins.inc...
1.238 [3609/24/719] Building IntrinsicsWebAssembly.h...
1.251 [3609/23/720] Building IntrinsicsSPIRV.h...
1.266 [3609/22/721] Building arm_mve_builtin_cg.inc...
1.275 [3609/21/722] Building IntrinsicsBPF.h...
1.294 [3609/20/723] Building IntrinsicsX86.h...
1.313 [3609/19/724] Building IntrinsicsLoongArch.h...
1.314 [3609/18/725] Building IntrinsicsHexagon.h...
1.335 [3609/17/726] Building arm_sve_builtin_cg.inc...
1.342 [3609/16/727] Building IntrinsicsPowerPC.h...
1.345 [3609/15/728] Building IntrinsicsNVPTX.h...
1.355 [3609/14/729] Building IntrinsicEnums.inc...
1.370 [3609/13/730] Building IntrinsicsXCore.h...
1.371 [3609/12/731] Building IntrinsicsMips.h...
1.374 [3609/11/732] Building arm_sve_builtins.inc...
1.383 [3609/10/733] Building IntrinsicsARM.h...
1.387 [3609/9/734] Building IntrinsicsDirectX.h...
1.389 [3609/8/735] Building IntrinsicsAMDGPU.h...
1.392 [3609/7/736] Building IntrinsicsVE.h...
1.396 [3609/6/737] Building IntrinsicsAArch64.h...
1.398 [3609/5/738] Building IntrinsicsR600.h...
1.398 [3609/4/739] Building IntrinsicsS390.h...
1.399 [3609/3/740] Building IntrinsicsRISCV.h...
1.443 [3609/2/741] Building IntrinsicImpl.inc...
1.527 [3609/1/742] Building ARMTargetParserDef.inc...
ninja: build stopped: subcommand failed.

```

</details>

https://github.com/llvm/llvm-project/pull/115099