### What this PR does / why we need it? Fix api in DeepSeekV2, aligning with the latest code of the main branch in vllm. ### Does this PR introduce _any_ user-facing change? N/A ### How was this patch tested? Test locally with deepseek-v2-lite, and will add CI by @Potabk. Plz update the model UT after this pr is merged, thx! cc @Potabk Signed-off-by: MengqingCao <cmq0113@163.com>