Revert "[lldb][DebugNames] Only skip processing of DW_AT_declarations for class/union types"
and two follow-up commits. The reason is the crash we've discovered when
processing -gsimple-template-names binaries. I'm committing a minimal
reproducer as a separate patch.
This reverts the following commits:
- 51dd4eaaa29683c16151f5168e7f8645acbd6e6c (#92328)
- 3d9d48523977af3590f7dd0edfd258454cb9e9cf (#93839)
- afe6ab7586f7078cc410f6162bd9851e48e2a286 (#94400)