[Feat]Make full graph mode compalible with MTP (#3276)

### What this PR does / why we need it?
Make the Full Graph mode can run with MTP.

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

### How was this patch tested?

- vLLM version: v0.11.0rc3
- vLLM main: https://github.com/vllm-project/vllm/commit/v0.11.0

Signed-off-by: anon189Ty <Stari_Falcon@outlook.com>

vllm_ascend/attention/mla_v1.py

@@ -175,7 +175,7 @@ M = TypeVar("M", bound=AscendMLAMetadata)
 class AscendMLAMetadataBuilder:
     # Does this backend/builder support ACL Graphs for attention (default: no).
     aclgraph_support: ClassVar[AttentionCGSupport] = \
-        AttentionCGSupport.UNIFORM_SINGLE_TOKEN_DECODE
+        AttentionCGSupport.UNIFORM_BATCH
     """
     NOTE: Please read the comment at the top of the file before trying to
     understand this class
@@ -209,7 +209,6 @@ class AscendMLAMetadataBuilder:
                 got {self.decode_threshold}"
 
         self.reorder_batch_threshold = self.decode_threshold
-
         if self.chunked_prefill_enabled:
             self.chunked_prefill_workspace_size = min(
                 # Max sure there is enough for 8 full length request or at least
@@ -427,10 +426,10 @@ class AscendMLAMetadataBuilder:
                     sin=sin,
                     cos=cos)
             else:
-                cos[:num_decodes,
+                cos[:num_decode_tokens,
                     ...] = self.cos_cache[input_positions].unsqueeze(
                         1).unsqueeze(2)
-                sin[:num_decodes,
+                sin[:num_decode_tokens,
                     ...] = self.sin_cache[input_positions].unsqueeze(
                         1).unsqueeze(2)
 
@@ -442,8 +441,8 @@ class AscendMLAMetadataBuilder:
                     max_seq_lens=max_seq_lens,
                     attn_mask=common_attn_metadata.spec_attn_mask,
                     actual_seq_lengths_q=actual_seq_lengths_q,
-                    sin=sin[:num_decodes, ...],
-                    cos=cos[:num_decodes, ...])
+                    sin=sin[:num_decode_tokens, ...],
+                    cos=cos[:num_decode_tokens, ...])
 
         return self.metadata_cls(  # type: ignore
             num_actual_tokens=num_actual_tokens,
@@ -469,7 +468,10 @@ class AscendMLAMetadataBuilder:
         attn_state: AscendAttentionState = AscendAttentionState.DecodeOnly,
         model: Optional[nn.Module] = None,
     ):
-        if attn_state == AscendAttentionState.DecodeOnly:
+        if attn_state in {
+                AscendAttentionState.DecodeOnly,
+                AscendAttentionState.SpecDecoding
+        }:
             attn_metadata = self.build(
                 common_prefix_len=0,
                 common_attn_metadata=common_attn_metadata,
@@ -477,7 +479,7 @@ class AscendMLAMetadataBuilder:
             )
         else:
             raise NotImplementedError(
-                "Currently we only support building dummy metadata for DecodeOnly state"
+                "Currently we only support building dummy metadata for DecodeOnly and SpecDecoding state"
             )
 
         attn_metadata.attn_state = attn_state
@@ -955,7 +957,8 @@ class AscendMLAImpl(MLAAttentionImpl):
 
         if attn_metadata.attn_state in [
                 AscendAttentionState.SpecDecoding,
-                AscendAttentionState.ChunkedPrefill
+                AscendAttentionState.ChunkedPrefill,
+                AscendAttentionState.DecodeOnly,
         ] and self.speculative_config is not None:
             # Use TND layout for pure SpecDecoding and SpecDecoding in ChunkedPrefill
             input_layout = "TND"