Nikhil Shinde

Fix compilation error in tensorflow/python/tfcompile_wrapper.cc on s390x

1

TensorFlow build was failing on s390x with following error: ``` tensorflow/python/tfcompile_wrapper.cc:55:44: error: calling 'getHostCPUName' with incomplete return type 'StringRef' 55 | std::move(target_cpu.empty() ? llvm::sys::getHostCPUName().str() | ^~~~~~~~~~~~~~~~~~~~~~~~~~~ external/llvm-project/llvm/include/llvm/TargetParser/Host.h:44:13: note: 'getHostCPUName' declared...