### What this PR does / why we need it?
fix bugs when mtp>1, and reorder input batch when mtp is not accepted.
### Does this PR introduce _any_ user-facing change?
no
### How was this patch tested?
by ci
- vLLM version: v0.10.2
- vLLM main:
52d0cb8458
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Signed-off-by: zouyida2052 <zouyida2002@gmail.com>