Merge pull request #15193 from sneaxiy/fix_cudnn_compatible_check

Fix cudnn compatible check

paddle/fluid/platform/device_context.cc

@@ -285,7 +285,7 @@ CUDADeviceContext::CUDADeviceContext(CUDAPlace place)
     if (dynload::HasCUDNN()) {
       auto local_cudnn_version = cudnn_dso_ver / 100;
       auto compile_cudnn_version = CUDNN_VERSION / 100;
-      if (local_cuda_version < compile_cuda_version) {
+      if (local_cudnn_version < compile_cudnn_version) {
         LOG_FIRST_N(WARNING, 1)
             << "WARNING: device: " << place_.device
             << ". The installed Paddle is compiled with CUDNN "