Tweak llvm-nm’s -undefined-only (aka -u) printing for Mach-O files

to just print the symbol name.  So it matches darwin’s nm(1) -u option.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214143 91177308-0d34-0410-b5e6-96231b3b80d8

tools/llvm-nm/llvm-nm.cpp

@@ -583,7 +583,7 @@ static void sortAndPrintSymbolList(SymbolicFile *Obj, bool printName,
         outs() << ArchiveName << ":";
       outs() << CurrentFilename << ": ";
     }
-    if (JustSymbolName) {
+    if (JustSymbolName || (UndefinedOnly && isa<MachOObjectFile>(Obj))) {
       outs() << I->Name << "\n";
       continue;
     }