[clang] [llvm] [clang][DebugInfo] Emit DW_AT_object_pointer on function declarations with explicit `this` (PR #122928)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `clang-x86_64-debian-fast` running on `gribozavr4` while building `clang,llvm` at step 5 "build-unified-tree".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/56/builds/16520

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

```
Step 5 (build-unified-tree) failure: build (failure)
...
  /// \returns \c nullptr if this \p Record should be skipped, or a pointer to
      ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
14 warnings generated.
22.694 [2055/96/3946] Copying llvm_debuginfo.ml to build area
22.713 [2054/96/3947] Copying llvm_debuginfo.mli to build area
22.718 [2053/96/3948] Building OCaml stub object file bitreader_ocaml.o
22.721 [2052/96/3949] Copying debuginfo_ocaml.c to build area
22.735 [2051/96/3950] Building OCaml stub object file analysis_ocaml.o
22.743 [2050/96/3951] Building OCaml stub object file bitwriter_ocaml.o
22.787 [2049/96/3952] Building OCaml stub object file debuginfo_ocaml.o
FAILED: bindings/ocaml/debuginfo/debuginfo_ocaml.o /b/1/clang-x86_64-debian-fast/llvm.obj/bindings/ocaml/debuginfo/debuginfo_ocaml.o 
cd /b/1/clang-x86_64-debian-fast/llvm.obj/bindings/ocaml/debuginfo && /usr/bin/ocamlfind ocamlc -c /b/1/clang-x86_64-debian-fast/llvm.obj/bindings/ocaml/debuginfo/debuginfo_ocaml.c -ccopt "-I/b/1/clang-x86_64-debian-fast/llvm.src/llvm/bindings/ocaml/debuginfo/../llvm -D_GNU_SOURCE -D_DEBUG -D_GLIBCXX_ASSERTIONS -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/b/1/clang-x86_64-debian-fast/llvm.obj/include -I/b/1/clang-x86_64-debian-fast/llvm.src/llvm/include  -DNDEBUG "
/b/1/clang-x86_64-debian-fast/llvm.obj/bindings/ocaml/debuginfo/debuginfo_ocaml.c: In function ‘llvm_dibuild_create_object_pointer_type’:
/b/1/clang-x86_64-debian-fast/llvm.obj/bindings/ocaml/debuginfo/debuginfo_ocaml.c:620:30: error: too few arguments to function ‘LLVMDIBuilderCreateObjectPointerType’
  620 |   LLVMMetadataRef Metadata = LLVMDIBuilderCreateObjectPointerType(
      |                              ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from /b/1/clang-x86_64-debian-fast/llvm.obj/bindings/ocaml/debuginfo/debuginfo_ocaml.c:23:
/b/1/clang-x86_64-debian-fast/llvm.src/llvm/include/llvm-c/DebugInfo.h:880:17: note: declared here
  880 | LLVMMetadataRef LLVMDIBuilderCreateObjectPointerType(LLVMDIBuilderRef Builder,
      |                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
22.795 [2049/95/3953] Building OCaml library llvm_analysis
22.795 [2049/94/3954] Building OCaml library llvm_bitreader
22.822 [2049/93/3955] Building OCaml library llvm_bitwriter
22.840 [2049/92/3956] Building CXX object lib/CodeGen/CMakeFiles/LLVMCodeGen.dir/MachineOutliner.cpp.o
22.848 [2049/91/3957] Building CXX object tools/clang/lib/ARCMigrate/CMakeFiles/obj.clangARCMigrate.dir/ObjCMT.cpp.o
In file included from /b/1/clang-x86_64-debian-fast/llvm.src/clang/lib/ARCMigrate/ObjCMT.cpp:9:
In file included from /b/1/clang-x86_64-debian-fast/llvm.src/clang/lib/ARCMigrate/Transforms.h:13:
In file included from /b/1/clang-x86_64-debian-fast/llvm.src/clang/include/clang/AST/RecursiveASTVisitor.h:17:
In file included from /b/1/clang-x86_64-debian-fast/llvm.src/clang/include/clang/AST/Attr.h:18:
In file included from /b/1/clang-x86_64-debian-fast/llvm.src/clang/include/clang/AST/Decl.h:17:
/b/1/clang-x86_64-debian-fast/llvm.src/clang/include/clang/AST/APValue.h:370:14: warning: parameter 'UninitArray' not found in the function declaration [-Wdocumentation]
  /// \param UninitArray Marker. Pass an empty UninitArray.
             ^~~~~~~~~~~
/b/1/clang-x86_64-debian-fast/llvm.src/clang/include/clang/AST/APValue.h:378:14: warning: parameter 'UninitStruct' not found in the function declaration [-Wdocumentation]
  /// \param UninitStruct Marker. Pass an empty UninitStruct.
             ^~~~~~~~~~~~
In file included from /b/1/clang-x86_64-debian-fast/llvm.src/clang/lib/ARCMigrate/ObjCMT.cpp:9:
In file included from /b/1/clang-x86_64-debian-fast/llvm.src/clang/lib/ARCMigrate/Transforms.h:13:
In file included from /b/1/clang-x86_64-debian-fast/llvm.src/clang/include/clang/AST/RecursiveASTVisitor.h:17:
In file included from /b/1/clang-x86_64-debian-fast/llvm.src/clang/include/clang/AST/Attr.h:18:
In file included from /b/1/clang-x86_64-debian-fast/llvm.src/clang/include/clang/AST/Decl.h:22:
/b/1/clang-x86_64-debian-fast/llvm.src/clang/include/clang/AST/ExternalASTSource.h:165:39: warning: empty paragraph passed to '\param' command [-Wdocumentation]
  /// specializations for the \param D.
                              ~~~~~~~~^
/b/1/clang-x86_64-debian-fast/llvm.src/clang/include/clang/AST/ExternalASTSource.h:165:38: warning: parameter 'D.' not found in the function declaration [-Wdocumentation]
  /// specializations for the \param D.
                                     ^~
/b/1/clang-x86_64-debian-fast/llvm.src/clang/include/clang/AST/ExternalASTSource.h:171:44: warning: empty paragraph passed to '\param' command [-Wdocumentation]
  /// args specified by \param TemplateArgs.

```

</details>

https://github.com/llvm/llvm-project/pull/122928