[misc] Add Torch profiler support for CPU-only devices

[DamonFool]

Hi all,

This is a follow up of #7451, which adds torch profiler support for CPU-only devices.

Before this patch, I got the following error on CPU-only devices.

INFO 08-23 01:59:55 api_server.py:315] Starting profiler...
INFO 08-23 01:59:55 server.py:128] Starting profiler...
(VllmWorkerProcess pid=19390) ERROR 08-23 01:59:55 multiproc_worker_utils.py:226] Exception in worker VllmWorkerProcess while processing method start_profile: 'CPUWorker' object has no attribute 'start_profile', Traceback (most recent call last):
(VllmWorkerProcess pid=19390) ERROR 08-23 01:59:55 multiproc_worker_utils.py:226]   File "/usr/local/lib/python3.10/dist-packages/vllm-0.5.4+cpu-py3.10-linux-x86_64.egg/vllm/executor/multiproc_worker_utils.py", line 222, in _run_worker_process
(VllmWorkerProcess pid=19390) ERROR 08-23 01:59:55 multiproc_worker_utils.py:226]     executor = getattr(worker, method)
(VllmWorkerProcess pid=19390) ERROR 08-23 01:59:55 multiproc_worker_utils.py:226] AttributeError: 'CPUWorker' object has no attribute 'start_profile'
(VllmWorkerProcess pid=19390) ERROR 08-23 01:59:55 multiproc_worker_utils.py:226]
INFO:     127.0.0.1:48766 - "POST /start_profile HTTP/1.1" 500 Internal Server Error

After this patch, the profiler runs OK.

Please review it.
Thanks.

[github-actions]

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[DamonFool]

The implication has just copied what @SolitaryThinker had done for cpu+gpu targets (removing cuda profiling of course).

[DamonFool]

/ready

[DamonFool]

Thanks @comaniac for the review.