make sure benchmark_* imports are the functions, not modules (#1594)

src/deepsparse/__init__.py

@@ -40,6 +40,7 @@
 from .subgraph_execute import *
 from .analyze import analyze
 from .evaluation.evaluator import evaluate
-from .benchmark import benchmark_model, benchmark_pipeline
+from .benchmark.benchmark_model import benchmark_model
+from .benchmark.benchmark_pipeline import benchmark_pipeline
 
 _analytics.send_event("python__init")