[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-sles-build-only` running on `rocm-worker-hw-04-sles` while building `clang` at step 5 "compile-openmp".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/140/builds/16198

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

```
Step 5 (compile-openmp) failure: build (failure)
...
1.042 [6242/32/794] Building DiagnosticCrossTUEnums.inc...
1.043 [6241/32/795] Linking CXX executable bin/mlir-tblgen
1.044 [6240/32/796] Building arm_cde_builtin_cg.inc...
1.044 [6239/32/797] Building BuiltinsX86_64.inc...
1.045 [6238/32/798] Building arm_fp16.inc...
1.048 [6237/32/799] Building AttrHasAttributeImpl.inc...
1.048 [6236/32/800] Building arm_sme_builtins_za_state.inc...
1.048 [6235/32/801] Building arm_neon.inc...
1.049 [6234/32/802] Building CXX11AttributeInfo.inc...
1.050 [6233/32/803] Building BuiltinsX86.inc...
FAILED: tools/clang/include/clang/Basic/BuiltinsX86.inc 
cd /home/botworker/bbot/builds/openmp-offload-sles-build/llvm.build && /home/botworker/bbot/builds/openmp-offload-sles-build/llvm.build/bin/clang-tblgen -gen-clang-builtins -I /home/botworker/bbot/builds/openmp-offload-sles-build/llvm.src/clang/include/clang/Basic -I/home/botworker/bbot/builds/openmp-offload-sles-build/llvm.src/clang/include -I/home/botworker/bbot/builds/openmp-offload-sles-build/llvm.build/tools/clang/include -I/home/botworker/bbot/builds/openmp-offload-sles-build/llvm.build/include -I/home/botworker/bbot/builds/openmp-offload-sles-build/llvm.src/llvm/include /home/botworker/bbot/builds/openmp-offload-sles-build/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/botworker/bbot/builds/openmp-offload-sles-build/llvm.src/clang/include/clang/Basic/BuiltinsX86.td:147:7: error: Unexpected header name
  def _m_prefetch : X86LibBuiltin<"void(void *)">;
      ^
1.051 [6233/31/804] Building arm_sme_streaming_attrs.inc...
1.052 [6233/30/805] Building BuiltinsHexagon.inc...
1.054 [6233/29/806] Building AttrList.inc...
1.056 [6233/28/807] Building arm_immcheck_types.inc...
1.056 [6233/27/808] Building AttrSubMatchRulesParserStringSwitches.inc...
1.056 [6233/26/809] Building AttrParserStringSwitches.inc...
1.057 [6233/25/810] Building AttrSpellingListIndex.inc...
1.057 [6233/24/811] Building AttrTemplateInstantiate.inc...
1.059 [6233/23/812] Building AttrParsedAttrKinds.inc...
1.060 [6233/22/813] Building DiagnosticSemaEnums.inc...
1.061 [6233/21/814] Building ArmSMEAttrDefs.h.inc...
1.062 [6233/20/815] Building ArmSVEDialect.cpp.inc...
1.062 [6233/19/816] Building ArmSMEEnums.cpp.inc...
1.065 [6233/18/817] Building arm_mve_builtins.inc...
1.066 [6233/17/818] Building ArmSVE.cpp.inc...
1.066 [6233/16/819] Building ArmSVE.h.inc...
1.067 [6233/15/820] Building arm_mve_builtin_aliases.inc...
1.068 [6233/14/821] Building AttrParsedAttrImpl.inc...
1.075 [6233/13/822] Building DiagnosticParseKinds.inc...
1.080 [6233/12/823] Building DiagnosticInstallAPIKinds.inc...
1.081 [6233/11/824] Building arm_mve_builtin_cg.inc...
1.082 [6233/10/825] Building arm_sve_streaming_attrs.inc...
1.091 [6233/9/826] Building DiagnosticSerializationKinds.inc...
1.099 [6233/8/827] Building SPIRVOpsDialect.cpp.inc...
1.102 [6233/7/828] Building IntrinsicImpl.inc...
1.131 [6233/6/829] Building arm_sve_sema_rangechecks.inc...
1.138 [6233/5/830] Building SPIRVOps.h.inc...
1.142 [6233/4/831] Building SPIRVOps.cpp.inc...
1.147 [6233/3/832] Building arm_sve_builtins.inc...
1.170 [6233/2/833] Building riscv_vector_builtin_cg.inc...
1.241 [6233/1/834] Building ARMTargetParserDef.inc...
ninja: build stopped: subcommand failed.

```

</details>

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