mtgpu: fix detector

[yeahdongcn]

❯ pytest -s test_mthreads.py
==================================================================== test session starts ====================================================================
collected 1 item                                                                                                                                            

test_mthreads.py::test_detect [Device(manufacturer=<ManufacturerEnum.MTHREADS: 'mthreads'>, index=0, name='MTT S80', uuid='2b7d56ad-43c9-89d9-703c-03c503e7fad4', driver_version='3.3.1-server', runtime_version=None, runtime_version_original=None, compute_capability=None, cores=8, cores_utilization=0, memory=16384, memory_used=0, memory_utilization=0.0, temperature=55, power=None, power_used=116384, appendix={'vgpu': False})]
PASSED

===================================================================== 1 passed in 0.05s =====================================================================

[yeahdongcn]

@thxCode Please take a look. Thanks.

[thxCode]

LGTM