rename files, added header guard, added namespace

[ROCm/composable_kernel commit: 88b77181aa]

src/include/functional2.hpp

@@ -1,7 +1,11 @@
-#pragma once
+#ifndef CK_FUNCTIONAL2_HPP
+#define CK_FUNCTIONAL2_HPP
+
 #include "functional.hpp"
 #include "Sequence.hpp"
 
+namespace ck {
+
 template <class>
 struct static_for_impl;
 
@@ -59,3 +63,6 @@ accumulate_on_sequence(Seq, Reduce f, Number<Init> /*initial_value*/)
 
     return result;
 }
+
+} // namespace ck
+#endif