Add an include guard to ninetoothed/utils.h

Author: voltjia

src/infiniop/ninetoothed/utils.h

@@ -1,3 +1,6 @@
+#ifndef __NINETOOTHED_UTILS__
+#define __NINETOOTHED_UTILS__
+
 #include <initializer_list>
 #include <limits>
 #include <type_traits>
@@ -68,3 +71,5 @@ class Tensor {
 };
 
 } // namespace ninetoothed
+
+#endif