[Bugfix][CPU] Fix broken AVX2 CPU TP support (vllm-project#17252)

Signed-off-by: Isotr0py <2037008807@qq.com>

Author: Isotr0py

vllm/distributed/device_communicators/cpu_communicator.py

@@ -22,7 +22,8 @@ def __init__(self,
         super().__init__(cpu_group, device, device_group, unique_name)
         self.dist_module = torch.distributed
 
-        if current_platform.get_cpu_architecture() == CpuArchEnum.X86:
+        if (current_platform.get_cpu_architecture() == CpuArchEnum.X86) \
+            and hasattr(torch.ops._C, "init_shm_manager"):
             self.dist_module = _CPUSHMDistributed(self)
 
     def all_reduce(self, input_):