[MM][Bugfix] Update hf_config to hf_text_config (#5319)

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

Following https://github.com/vllm-project/vllm-ascend/pull/5205, update
`hf_config` to `hf_text_config`.

Find more details at
https://github.com/vllm-project/vllm-ascend/pull/5205#issuecomment-3675417534
and
https://github.com/vllm-project/vllm-ascend/pull/5205#issuecomment-3677920872.

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

### How was this patch tested?

- vLLM version: release/v0.13.0
- vLLM main:
5fbfa8d9ef

Signed-off-by: shen-shanshan <467638484@qq.com>

vllm_ascend/attention/sfa_v1.py

@@ -149,7 +149,7 @@ class AscendSFAMetadataBuilder(MLACommonMetadataBuilder[AscendSFAMetadata]):
 
         self.rope_dim = self.model_config.hf_text_config.qk_rope_head_dim
         self.enable_sfa_cp = enable_sp() and \
-            hasattr(self.model_config.hf_config, "index_topk")
+            hasattr(self.model_config.hf_text_config, "index_topk")
 
         assert not (
             self.enable_sfa_cp
@@ -963,7 +963,7 @@ class AscendSFAImpl(MLAAttentionImpl):
         # Dispose tensor from the original o_proj
         dispose_layer(self.o_proj)
         # Construct the new o_proj using ReplicatedLinear
-        config = vllm_config.model_config.hf_config
+        config = vllm_config.model_config.hf_text_config
         new_o_proj = ReplicatedLinear(config.num_attention_heads *
                                       config.v_head_dim,
                                       config.hidden_size,