Remove including of cmath (#551)

* Let cmath included when compiling host codes in math_v2.hpp

* Remove including of cmath in device_base.hpp and device_permute.hpp

include/ck/tensor_operation/gpu/device/device_base.hpp

@@ -3,7 +3,6 @@
 
 #pragma once
 
-#include <cmath>
 #include <string>
 #include <sstream>
 

include/ck/tensor_operation/gpu/device/device_permute.hpp

@@ -4,7 +4,6 @@
 #pragma once
 
 #include <array>
-#include <cmath>
 #include <memory>
 #include <type_traits>
 

include/ck/utility/math_v2.hpp

@@ -3,7 +3,9 @@
 
 #pragma once
 
+#ifndef __HIP_DEVICE_COMPILE__
 #include <cmath>
+#endif
 
 #include "ck/utility/data_type.hpp"
 #include "ck/utility/type.hpp"