fix profile run for vl model (#5136)

### What this PR does / why we need it?

### Does this PR introduce _any_ user-facing change?

### How was this patch tested?

- vLLM version: v0.12.0
- vLLM main:
ad32e3e19c

---------

Signed-off-by: 李少鹏 <lishaopeng21@huawei.com>

vllm_ascend/worker/worker_v1.py

@@ -232,6 +232,7 @@ class NPUWorker(WorkerBase):
         # Init ModelRunner here, so that we have access to self.device.
         self.model_runner = NPUModelRunner(self.vllm_config, self.device)
 
+    @torch.inference_mode()
     def determine_available_memory(self) -> int:
         # Profile the memory usage of the model and get the maximum number of
         # cache blocks that can be allocated with the remaining free memory.