[main][Refactor] Remove with_prefill parameter from set_ascend_forward_context (#5094)

Removes the redundant `with_prefill` parameter from
`set_ascend_forward_context` to align the interface with vLLM's
`set_forward_context` for future refactoring.
- vLLM version: v0.12.0
- vLLM main:
ad32e3e19c

---------

Signed-off-by: SlightwindSec <slightwindsec@gmail.com>
Signed-off-by: Slightwind <slightwindsec@gmail.com>
Co-authored-by: zzzzwwjj <34335947+zzzzwwjj@users.noreply.github.com>

vllm_ascend/spec_decode/mtp_proposer.py

@@ -299,7 +299,6 @@ class MtpProposer(Proposer):
                     attn_metadata,
                     self.vllm_config,
                     num_tokens=num_tokens,
-                    with_prefill=with_prefill,
                     num_tokens_across_dp=num_tokens_across_dp,
                     num_actual_tokens=0,
                     aclgraph_runtime_mode=aclgraph_runtime_mode,
@@ -779,7 +778,6 @@ class MtpProposer(Proposer):
                     attn_metadata,
                     self.vllm_config,
                     num_tokens=num_input_tokens,
-                    with_prefill=with_prefill,
                     num_tokens_across_dp=num_tokens_across_dp,
                     aclgraph_runtime_mode=aclgraph_runtime_mode,
                     batch_descriptor=batch_descriptor,