According to CUDA 9.2 Release Notes, cublas_device is deprecated and will be removed in the next release. That is also described in !2296 (merged).
Therefore, the condition of finding cublas_device should be that CUDA version is greater than 5.0 and less than 9.2 (not containing).
Issue: #18290 (closed)
Topic-rename: FindCUDA-deprecate-cublas_device