improvement: collecting gpu compute capability automatically

[gabriellaraujocoding]

Some people are struggling to compile and run NPB-GPU with CUDA because they are not providing the compute capability of their GPUs in the make.def file.

In this commit, we introduce an improvement to NPB-GPU where the NPB-GPU automatically collects the compute capability of the GPU specified in the file gpu.config (GPU_DEVICE).

[dalvangriebler]

Thanks @gabriellaraujo1903