[libtpu] Fix memory management bug in GetLibTpuInitArguments().

We save the raw pointers from 'args' into 'arg_ptrs' and return both vectors, so we should return 'std::move(args)' instead of making an implicit copy. I thought it would do this automatically but it empirically doesn't; I guess the std::pair screws up copy elision.

I also 'std::move(arg_ptrs)' for good measure, but I don't think this is necessary for correctness.

PiperOrigin-RevId: 360813200
Change-Id: Icfdf043883239d33777f2330f981a19b89c426ce

tensorflow/core/tpu/tpu_initializer_helper.cc

@@ -87,7 +87,7 @@ GetLibTpuInitArguments() {
     arg_ptrs.push_back(args[i].data());
   }
 
-  return {args, arg_ptrs};
+  return {std::move(args), std::move(arg_ptrs)};
 }
 
 }  // namespace tpu