### What this PR does / why we need it? 1. Replace manual memory cleanup with passing parameter. 2. FusedMoEPrepareAndFinalizeWithMC2 inherits All2All avoid duplicated code. ### Does this PR introduce _any_ user-facing change? No ### How was this patch tested? e2e & ut - vLLM version: v0.11.0rc3 - vLLM main: https://github.com/vllm-project/vllm/commit/v0.11.0 Signed-off-by: Pr0Wh1teGivee <calvin_zhu0210@outlook.com>