[DebugInfo] Add a TargetFuncName field in DISubprogram for

specifying DW_AT_trampoline as a string. Also update the signature
of DIBuilder::createFunction to reflect this addition.

Differential Revision: https://reviews.llvm.org/D123697

llvm/lib/Bitcode/Writer/BitcodeWriter.cpp

@@ -1822,6 +1822,7 @@ void ModuleBitcodeWriter::writeDISubprogram(const DISubprogram *N,
   Record.push_back(N->getThisAdjustment());
   Record.push_back(VE.getMetadataOrNullID(N->getThrownTypes().get()));
   Record.push_back(VE.getMetadataOrNullID(N->getAnnotations().get()));
+  Record.push_back(VE.getMetadataOrNullID(N->getRawTargetFuncName()));
 
   Stream.EmitRecord(bitc::METADATA_SUBPROGRAM, Record, Abbrev);
   Record.clear();