Replaced Intel compiler option -parallel with -mt_mpi

The option -parallel has unwanted side effects on some systems as it
enables optimizations that produce wrong results on such systems.

cmake/compilerflags.cmake

@@ -4,7 +4,7 @@ if (${CMAKE_Fortran_COMPILER_ID} MATCHES "Intel")
    if (${CMAKE_Fortran_COMPILER_VERSION} VERSION_LESS "14.1.0.0")
       set(CMAKE_Fortran_FLAGS "${CMAKE_Fortran_FLAGS} -mkl -r8 -openmp")
    else()
-      set(CMAKE_Fortran_FLAGS "${CMAKE_Fortran_FLAGS} -mkl -r8 -qopenmp -parallel")
+      set(CMAKE_Fortran_FLAGS "${CMAKE_Fortran_FLAGS} -mkl -r8 -qopenmp -mt_mpi")
    endif()     
    set(CMAKE_Fortran_FLAGS_RELEASE "${CMAKE_Fortran_FLAGS_RELEASE} -xHost -O4")
    set(CMAKE_Fortran_FLAGS_DEBUG "${CMAKE_Fortran_FLAGS_DEBUG} -C -traceback -O0 -g -ftrapuv -check uninit -check pointers -CB ")