message: [OpenMP] Add entry for Intel Compiler 18
  Patch by Simon Convent
diff: #define KMP_COMPILER "Intel C++ Compiler 16.0"
  #elif __INTEL_COMPILER == 1700
  #define KMP_COMPILER "Intel C++ Compiler 17.0"
  +#elif __INTEL_COMPILER == 1800
  +#define KMP_COMPILER "Intel C++ Compiler 18.0"
  #elif __INTEL_COMPILER == 9998
  #define KMP_COMPILER "Intel C++ Compiler mainline"
  #elif __INTEL_COMPILER == 9999
  