[AsmPrinter] Rename a comment of .gdb_index entry

[MaskRay]

Summary

The comment refers to the property as "Kind:". However, in gdb,

https://sourceware.org/gdb//onlinedocs/gdb/Index-Section-Format.html names it "attributes",
gdb/dwarf2read.c:dw2_symtab_iter_next refers to the whole value as "cu_index_and_attrs"

Change it to Attributes: for consistency.

[dblaikie]

Sounds good to me. Where possible it's great to quote the specs more than the source code - did you happen across any spec for gnu_pubnames themselves? Or only the gdb-index they're used to create (& that's good too - having consistency of naming between gnu_pubnames and gdb_index certainly helps)

[MaskRay]

Update description

llvm/trunk/lib/CodeGen/AsmPrinter/DwarfDebug.cpp

for (const auto &GI : Globals) {
     const DIE *Entity = GI.second;
 
     Asm->OutStreamer->AddComment("DIE offset");
     Asm->emitInt32(Entity->getOffset());
 
     if (GnuStyle) {
       dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheU, Entity);
       Asm->OutStreamer->AddComment(
-          Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " +
-          dwarf::GDBIndexEntryLinkageString(Desc.Linkage));
+          Twine("Attributes: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) +
+          ", " + dwarf::GDBIndexEntryLinkageString(Desc.Linkage));
       Asm->emitInt8(Desc.toBits());
     }
 
     Asm->OutStreamer->AddComment("External Name");
     Asm->OutStreamer->EmitBytes(StringRef(Name, GI.getKeyLength() + 1));
   }
 
   Asm->OutStreamer->AddComment("End Mark");

llvm/trunk/test/DebugInfo/X86/gnu-public-names.ll

 ; }
 ; }
 ;
 ; int f7() {
 ;   return i + *f3() + inner::b + outer::c;
 ; }
 
 ; ASM: .section        .debug_gnu_pubnames
-; ASM: .byte   32                      # Kind: VARIABLE, EXTERNAL
+; ASM: .byte   32                      # Attributes: VARIABLE, EXTERNAL
 ; ASM-NEXT: .asciz  "global_variable"       # External Name
 
 ; ASM: .section        .debug_gnu_pubtypes
 ; ASM: .byte   16                      # Kind: TYPE, EXTERNAL
 ; ASM-NEXT: .asciz  "C"                     # External Name
 
 ; CHECK: .debug_info contents:
 ; CHECK: Compile Unit: