[llvm] [llvm-debuginfo-analyzer] Add support for DW_AT_GNU_template_name. (PR #115724)

[Carlos Alberto Enciso via llvm-commits]

CarlosAlbertoEnciso wrote:

For the given test case, GCC and Clang generate the following DWARF
```
...
DW_TAG_GNU_template_template_param
     DW_AT_name	("TemplateTemplateType")
     DW_AT_GNU_template_name	("Bar")
...
DW_TAG_GNU_template_template_param
     DW_AT_name	("TemplateType")
     DW_AT_GNU_template_name	("Foo")
...
```
The `--attribute=typename` adds the `DW_AT_name` to the printed logical view.
```
clang++ -c -g -O0 template.cpp -o template-clang.o
llvm-debuginfo-analyzer --print=elements --attribute=typename template-clang.o
```

```
Logical View:
           {File} 'template-clang.o'

             {CompileUnit} 'template.cpp'
     1         {Class} 'Foo<int>'
                 {TemplateType} 'T' -> 'int'
     1           {Member} private 'Member' -> 'int'
     4         {Class} 'Bar<Foo>'
                 {TemplateTemplate} 'TemplateType' -> 'Foo'          <-- DW_AT_name value
     5           {Member} private 'Int' -> 'Foo<int>'
     9         {Class} 'Baz<Bar>'
                 {TemplateTemplate} 'TemplateTemplateType' -> 'Bar'  <-- DW_AT_name value
    10           {Member} private 'Foo' -> 'Bar<Foo>'
    13         {TypeAlias} 'Example' -> 'Baz<Bar>'
    14         {Variable} extern 'TT' -> 'Example'
```

https://github.com/llvm/llvm-project/pull/115724