[Compile] Reset custom allreduce flag in O2 mode to NONE (#3081)

This PR resets the default IPC allreduce strategy under O2 mode
to NONE for platform compatability.

Author: MasterJH5574

python/mlc_llm/interface/compiler_flags.py

@@ -210,7 +210,7 @@ def from_str(source: str) -> "ModelConfigOverride":
         faster_transformer=False,
         cudagraph=True,
         cutlass=True,
-        ipc_allreduce_strategy=IPCAllReduceStrategyType.AUTO,
+        ipc_allreduce_strategy=IPCAllReduceStrategyType.NONE,
     ),
     "O3": OptimizationFlags(
         flashinfer=True,