Compilation with GCC fails due to use of deprecated functions

[robert-mijakovic]

I tried to compile IMB with GCC 13.2.0 but it failed due to use of a deprecated function(s) std::binary_function.

In file included from ./benchmark_suites_collection.h:36,
                 from MPI1/MPI1_suite.cpp:44:
./utils.h:75:42: error: 'template<class _Arg1, class _Arg2, class _Result> struct std::binary_function' is deprecated [-Werror=deprecated-declarations]
   75 |     struct case_insens_cmp : public std::binary_function<std::string, std::string, bool> {
      |                                          ^~~~~~~~~~~~~~~
In file included from /spack/release/24.1.0/opt/x86_64/gcc/13.2.0-gcc-itoa7pi/lib/gcc/x86_64-pc-linux-gnu/13.2.0/../../../../include/c++/13.2.0/bits/stl_tree.h:65,
                 from /spack/release/24.1.0/opt/x86_64/gcc/13.2.0-gcc-itoa7pi/lib/gcc/x86_64-pc-linux-gnu/13.2.0/../../../../include/c++/13.2.0/set:62,
                 from MPI1/MPI1_suite.cpp:37:
/spack/release/24.1.0/opt/x86_64/gcc/13.2.0-gcc-itoa7pi/lib/gcc/x86_64-pc-linux-gnu/13.2.0/../../../../include/c++/13.2.0/bits/stl_function.h:131:12: note: declared here
  131 |     struct binary_function
      |            ^~~~~~~~~~~~~~~
cc1plus: all warnings being treated as errors
make[1]: *** [MPI1/Makefile.MPI1.mk:108: MPI1/CPU/MPI1_suite.o] Error 1
make[1]: Leaving directory '/home/robert/archives/mpi-benchmarks-IMB-v2021.8/src_cpp'
make: *** [Makefile:36: IMB-MPI1] Error 2

Can you please have a look and fix the code?