[kernel] remove spec use of isnan isinf for cxx1 (opensuse build)
#define SICONOS_ISNAN
#if __cplusplus >= 201103L
#include <cmath>
-using std::isnan;
-using std::isinf;
#else
#if ((!defined(_MSC_VER)) && (!defined( __SUNPRO_CC)))
#include <cmath>
