improve CUDA device uniqueID by adding pciDomainID as prefix.

[hibagus]

This is needed for multi-socket system where pciBusID and pciDeviceID can be the same on two different pci domains.
Now, the uniqueID will be the same as what nvidia-smi gives on Bus-Id

An example is below: GPU0 and GPU4 have the same pciDeviceID and pciBusID. They are connected to a different sockets, and thus they are different in pciDomainID. This means that there are more than one GPUs that have the same UniqueID and only one will be used for mining.

+-----------------------------------------------------------------------------+
| NVIDIA-SMI 440.33.01    Driver Version: 440.33.01    CUDA Version: 10.2     |
|-------------------------------+----------------------+----------------------+
| GPU  Name        Persistence-M| Bus-Id        Disp.A | Volatile Uncorr. ECC |
| Fan  Temp  Perf  Pwr:Usage/Cap|         Memory-Usage | GPU-Util  Compute M. |
|===============================+======================+======================|
|   0  XXXXXXXXX  On            | 00000004:04:00.0 Off |                    0 |
| N/A   25C    P0    34W / xxxW |      0MiB / 16160MiB |      0%      Default |
+-------------------------------+----------------------+----------------------+
|   1  XXXXXXXXX   On           | 00000004:05:00.0 Off |                    0 |
| N/A   27C    P0    35W / xxxW |      0MiB / 16160MiB |      0%      Default |
+-------------------------------+----------------------+----------------------+
|   2  XXXXXXXXX   On           | 00000035:03:00.0 Off |                    0 |
| N/A   23C    P0    34W / xxxW |      0MiB / 16160MiB |      0%      Default |
+-------------------------------+----------------------+----------------------+
|   3  XXXXXXXXX   On           | 00000035:04:00.0 Off |                    0 |
| N/A   28C    P0    36W / xxxW |      0MiB / 16160MiB |      0%      Default |
+-------------------------------+----------------------+----------------------+
                                                                               
+-----------------------------------------------------------------------------+
| Processes:                                                       GPU Memory |
|  GPU       PID   Type   Process name                             Usage      |
|=============================================================================|
|  No running processes found                                                 |
+-----------------------------------------------------------------------------+

Thanks!