Fix MTP error when enabling two-batch overlap (#7569)

python/sglang/srt/model_executor/cuda_graph_runner.py

@@ -168,7 +168,7 @@ def get_batch_sizes_to_capture(model_runner: ModelRunner):
         capture_bs += [model_runner.req_to_token_pool.size]
 
     if server_args.enable_two_batch_overlap:
-        capture_bs = [bs for bs in capture_bs if bs >= 2]
+        capture_bs = [bs for bs in capture_bs if bs % 2 == 0]
 
     if server_args.cuda_graph_max_bs:
         capture_bs = [bs for bs in capture_bs if bs <= server_args.cuda_graph_max_bs]