Fix warnings (#2358)

Changming Sun · wschin · commit 034921bd574c · 2019-09-26T12:29:38.000-07:00
diff --git a/onnx/common/common.h b/onnx/common/common.h
@@ -3,10 +3,4 @@
 
 #pragma once
 
-namespace ONNX_NAMESPACE {
-#ifdef _WIN32
-#define ONNX_UNUSED_PARAMETER(x) (x)
-#else
 #define ONNX_UNUSED_PARAMETER(x) (void)(x)
-#endif
-} // namespace ONNX_NAMESPACE
