[CUDA][Clang][Bugfix] Add missing CUDA 9.2 case

[gtbercea]

Summary

The bug was reported on the OpenMP-dev list:

.../obj-release/lib/clang/9.0.0/include/__clang_cuda_intrinsics.h:173:35: error: 'nvvm_shfl_sync_idx_i32' needs target feature ptx60|ptx61|ptx63|ptx64
MAKE_SYNC_SHUFFLES(shfl_sync, nvvm_shfl_sync_idx_i32,

This problem occurs when trying to compile a .cu file that requires a newer ptx version (>ptx60 in this case) than ptx42.

lib/Driver/ToolChains/Cuda.cpp

void CudaToolChain::addClangTargetOptions(
   const char *PtxFeature = nullptr;
   switch(CudaInstallation.version()) {
     case CudaVersion::CUDA_101:
       PtxFeature = "+ptx64";
       break;
     case CudaVersion::CUDA_100:
       PtxFeature = "+ptx63";
       break;
+    case CudaVersion::CUDA_92:
+      PtxFeature = "+ptx61";
+      break;
     case CudaVersion::CUDA_91:
       PtxFeature = "+ptx61";
       break;
     case CudaVersion::CUDA_90:
       PtxFeature = "+ptx60";
       break;
     default:
       PtxFeature = "+ptx42";