Add --speculative-moe-runner-backend server arg (#10183)

python/sglang/srt/layers/moe/topk.py

@@ -38,10 +38,7 @@ from sglang.srt.eplb.expert_location_dispatch import (
     ExpertLocationDispatchInfo,
     topk_ids_logical_to_physical,
 )
-from sglang.srt.layers.moe import (
-    get_moe_runner_backend,
-    should_use_flashinfer_trtllm_moe,
-)
+from sglang.srt.layers.moe import get_moe_runner_backend
 from sglang.srt.utils import (
     cpu_has_amx_support,
     get_bool_env_var,
@@ -257,7 +254,7 @@ class TopK(CustomOp):
         elif get_moe_runner_backend().is_triton_kernels():
             output_format = TopKOutputFormat.TRITON_KERNEL
         elif (
-            should_use_flashinfer_trtllm_moe()
+            get_moe_runner_backend().is_flashinfer_trtllm()
             or get_moe_runner_backend().is_flashinfer_mxfp4()
         ):
             output_format = TopKOutputFormat.BYPASSED