[Bug] Fix vLLM config is not set error (#29999)

Signed-off-by: yewentao256 <zhyanwentao@126.com>

vllm/model_executor/layers/quantization/utils/flashinfer_utils.py

@@ -247,6 +247,11 @@ def flashinfer_cutlass_moe_fp8(
     assert quant_config is not None
 
     # Construct modular kernel with block-scale support when requested.
+    parallel_config = getattr(
+        getattr(layer, "vllm_config", None),
+        "parallel_config",
+        None,
+    )
     fused_experts = mk.FusedMoEModularKernel(
         build_flashinfer_fp8_cutlass_moe_prepare_finalize(
             moe=moe, use_deepseek_fp8_block_scale=use_deepseek_fp8_block_scale
@@ -257,6 +262,7 @@ def flashinfer_cutlass_moe_fp8(
             out_dtype=hidden_states.dtype,
             use_deepseek_fp8_block_scale=use_deepseek_fp8_block_scale,
         ),
+        parallel_config=parallel_config,
     )
 
     return fused_experts(