Move mla to ops module (#4575)

Move mla custom op to correct module
- vLLM version: v0.11.2
- vLLM main: https://github.com/vllm-project/vllm/commit/v0.11.2

Signed-off-by: wangxiyuan <wangxiyuan1007@gmail.com>

vllm_ascend/utils.py

@@ -648,7 +648,6 @@ def register_ascend_customop(vllm_config: Optional[VllmConfig] = None):
         return
     from vllm.model_executor.custom_op import CustomOp
 
-    from vllm_ascend.models.layers.mla import AscendMultiHeadLatentAttention
     from vllm_ascend.ops.activation import AscendQuickGELU, AscendSiluAndMul
     from vllm_ascend.ops.fused_moe.fused_moe import (AscendFusedMoE,
                                                      AscendSharedFusedMoE)
@@ -658,6 +657,7 @@ def register_ascend_customop(vllm_config: Optional[VllmConfig] = None):
                                         AscendQKVParallelLinear,
                                         AscendReplicatedLinear,
                                         AscendRowParallelLinear)
+    from vllm_ascend.ops.mla import AscendMultiHeadLatentAttention
     from vllm_ascend.ops.rotary_embedding import (
         AscendDeepseekScalingRotaryEmbedding, AscendMRotaryEmbedding,
         AscendRotaryEmbedding, AscendYaRNRotaryEmbedding)