make ginQueueDepth configurable

[GuangguanWang]

make ginQueueDepth configurable as GIN PROXY mode requires ginQueueDepth = 0

relative error msg when run in GIN PROXY mode with 1024 ginQueueDepth

Traceback (most recent call last):
  File "/root/miniconda3/envs/deepepv2/lib/python3.10/site-packages/torch/multiprocessing/spawn.py", line 87, in _wrap
    fn(i, *args)
  File "/root/miniconda3/envs/deepepv2/lib/python3.10/site-packages/torch/utils/_contextlib.py", line 124, in decorate_context
    return func(*args, **kwargs)
  File "/mnt/deepep-v2/DeepEP/tests/elastic/test_barrier.py", line 36, in test_loop
    buffer = deep_ep.ElasticBuffer(
  File "/root/miniconda3/envs/deepepv2/lib/python3.10/site-packages/deep_ep/buffers/elastic.py", line 217, in __init__
    self.runtime = _C.ElasticBuffer(group.rank(), group.size(),
RuntimeError: NCCL exception (/mnt/deepep-v2/DeepEP/csrc/kernels/backend/nccl.cu:105): 5 (GIN_IB_PROXY does not support specifying qp depth)

[isayoften]

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