[main] mlp weight prefetch in Qwen Dense Models (#2816)

### What this PR does / why we need it?
This PR prefetchs the weight of mlp layers in Qwen Dense Models to
optimize the performance in Decode phase mainly.

### Does this PR introduce _any_ user-facing change?
 No.

### How was this patch tested?
CI passed with new added/existing test.

- vLLM version: main
- vLLM main:
a1213fae5f

Signed-off-by: rjg-lyh <1318825571@qq.com>
Co-authored-by: Shuming19 <313093131@qq.com>

vllm_ascend/ops/linear.py

@@ -390,6 +390,7 @@ class AscendRowParallelLinear(RowParallelLinear):
                                                       input_parallel,
                                                       bias=bias_)
             output = torch.ops.vllm.maybe_pad_and_reduce(output_parallel)
+            torch.ops.vllm.maybe_prefetch_mlp_gate_up_proj(output, self.prefix)
 
         output_bias = self.bias if self.skip_bias_add else None