[Bugfix] Support for mlapo in deepseekv3.1 w4a8 (#4828)

### What this PR does / why we need it?
Support for mlapo in deepseekv3.1 w4a8, since the csrc of mlapo requires the input args `enable_inner_out` and `inner_out`, we add the dummy args here

- vLLM version: v0.12.0
- vLLM main:
vllm-project/vllm@ad32e3e

Signed-off-by: GDzhu01 <[email protected]>
Co-authored-by: Mengqing Cao <[email protected]>

Author: GDzhu01

vllm_ascend/attention/mla_v1.py

@@ -1064,7 +1064,8 @@ def _process_weights_for_fused_mlapo(self, act_dtype: torch.dtype):
 
         device = self.q_proj.weight.device
         self.gamma1 = self.q_a_layernorm.weight.data
-        self.beta1 = self.q_a_layernorm.bias.data
+        self.beta1 = torch.zeros_like(self.gamma1) if (
+            _bias := self.q_a_layernorm.bias) is None else _bias.data
         self.gamma2 = self.kv_a_layernorm.weight.data
         self.quant_scale0 = self.fused_qkv_a_proj.input_scale.data
         self.quant_offset0 = self.fused_qkv_a_proj.input_offset.data
@@ -1460,7 +1461,8 @@ def _mla_decode_preprocess(self, hidden_states, kv_cache, attn_metadata):
             kv_cache_out0=decode_k_nope,
             q_out1=decode_q_pe,
             kv_cache_out1=decode_k_pe,
-        )
+            enable_inner_out=False,
+            inner_out=torch.tensor([], device=hidden_states.device))
         decode_q_nope = decode_q_nope.view(bsz, self.num_heads,
                                            self.kv_lora_rank)
         decode_q_pe = decode_q_pe.view(bsz, self.num_heads, -1)