Drop torchair (#4814)

aclgraph is stable and fast now. Let's drop torchair graph mode now.

TODO: some logic to adapt torchair should be cleaned up as well. We'll
do it in the following PR.

- vLLM version: v0.12.0
- vLLM main:
ad32e3e19c

Signed-off-by: wangxiyuan <wangxiyuan1007@gmail.com>
Co-authored-by: Mengqing Cao <cmq0113@163.com>

examples/run_dp_server.sh

@@ -27,5 +27,4 @@ vllm serve Qwen/Qwen1.5-MoE-A2.7B  \
   --max-num-batched-tokens 4096 \
   --gpu-memory-utilization 0.9 \
   --trust-remote-code \
-  --enforce-eager \
-  --additional-config '{"torchair_graph_config":{"enabled":false, "use_cached_graph":false}}'
+  --enforce-eager