[NFC][NVPTX] Remove dead override

[ldrumm]

Summary

After 68f2218e1e, NVPTXTargetObjectFile::Initialize is an empty wrapper
of the parent method. Get rid of it.

llvm/lib/Target/NVPTX/NVPTXTargetObjectFile.h

 namespace llvm {
 
 class NVPTXTargetObjectFile : public TargetLoweringObjectFile {
 public:
   NVPTXTargetObjectFile() = default;
 
   ~NVPTXTargetObjectFile() override;
 
-  void Initialize(MCContext &ctx, const TargetMachine &TM) override {
-    TargetLoweringObjectFile::Initialize(ctx, TM);
-  }
-
   MCSection *getSectionForConstant(const DataLayout &DL, SectionKind Kind,
                                    const Constant *C,
                                    Align &Alignment) const override {
     return ReadOnlySection;
   }
 
   MCSection *getExplicitSectionGlobal(const GlobalObject *GO, SectionKind Kind,
                                       const TargetMachine &TM) const override {