[MoE][TorchAir] Remove FusedMoEState (#4927)

### What this PR does / why we need it?
Remove FusedMoEState which is used by torchair.

### Does this PR introduce _any_ user-facing change?
No

### How was this patch tested?
e2e & ut

- vLLM version: v0.12.0
- vLLM main:
vllm-project/vllm@ad32e3e

Signed-off-by: weichen <[email protected]>

Author: Pr0Wh1teGivee

vllm_ascend/ascend_forward_context.py

@@ -19,15 +19,6 @@
     WeightPrefetchMethod = None
 
 
-class FusedMoEState(Enum):
-    AllGather = 0
-    All2All = 1
-    MC2 = 2
-    AllGatherEP = 3
-    NaiveMulticast = 4
-    All2AllSeq = 5
-
-
 class MoECommType(Enum):
     ALLGATHER = 0
     MC2 = 1