[fix]修复开启并行解码后，打印"Current platform rocm does not have 'Event' attribute"问题

vllm/spec_decode/metrics.py

@@ -86,9 +86,11 @@ class AsyncMetricsCollector:
         if isinstance(device_type, torch.device):
             torch.cuda.set_device(device_type)
             device_type = device_type.type
-        stream = current_platform.Stream
-        if stream is not None:
-            self._copy_stream = stream()
+        # stream = current_platform.Stream
+        # if stream is not None:
+        #     self._copy_stream = stream()
+        if device_type == 'cuda':
+            self._copy_stream = torch.cuda.Stream()
 
         pin_memory = is_pin_memory_available()
         self._aggregate_num_accepted_tokens = torch.tensor(
@@ -99,8 +101,8 @@ class AsyncMetricsCollector:
     def maybe_collect_rejsample_metrics(
             self, k: int) -> Optional[SpecDecodeWorkerMetrics]:
         # Skip for any platform that doesn't have device Event
-        if current_platform.Event is None:
-            return None
+        # if current_platform.Event is None:
+        #    return None
 
         # If a copy was initiated in the previous call, collect and return.
         if self._in_flight_copy is not None: