Add missing implementation to one of the Mat_<_Tp> constructor. (#5945)

modules/core/include/opencv2/core/mat.inl.hpp

@@ -1338,6 +1338,11 @@ Mat_<_Tp>::Mat_(int _dims, const int* _sz, const _Tp& _s)
     : Mat(_dims, _sz, DataType<_Tp>::type, Scalar(_s))
 {}
 
+template<typename _Tp> inline
+Mat_<_Tp>::Mat_(int _dims, const int* _sz, _Tp* _data, const size_t* _steps)
+    : Mat(_dims, _sz, DataType<_Tp>::type, _data, _steps)
+{}
+
 template<typename _Tp> inline
 Mat_<_Tp>::Mat_(const Mat_<_Tp>& m, const Range* ranges)
     : Mat(m, ranges)