### 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>