Revert "[lldb] Fix handling of DW_AT_decl_file according to D91014"

This reverts commit 7ec7876.

Non-x86_64 non-Linux bots broke by the testcase.

Author: jankratochvil

lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp

@@ -2201,8 +2201,7 @@ size_t DWARFASTParserClang::ParseChildEnumerators(
             case DW_AT_description:
             default:
             case DW_AT_decl_file:
-              decl.SetFile(attributes.CompileUnitAtIndex(i)->GetFile(
-                  form_value.Unsigned()));
+              decl.SetFile(die.GetCU()->GetFile(form_value.Unsigned()));
               break;
             case DW_AT_decl_line:
               decl.SetLine(form_value.Unsigned());

lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp

@@ -3126,8 +3126,8 @@ VariableSP SymbolFileDWARF::ParseVariableDIE(const SymbolContext &sc,
       continue;
     switch (attr) {
     case DW_AT_decl_file:
-      decl.SetFile(
-          attributes.CompileUnitAtIndex(i)->GetFile(form_value.Unsigned()));
+      decl.SetFile(sc.comp_unit->GetSupportFiles().GetFileSpecAtIndex(
+          form_value.Unsigned()));
       break;
     case DW_AT_decl_line:
       decl.SetLine(form_value.Unsigned());