PGI-Fortran support

We now have the PGI Fortran compiler on EVE (https://git.ufz.de/it/eve/software/-/issues/176). ATM there are some problems/bugs that need to be resolved in order to make it work:

• we need a load-script for the PGI compiler on EVE

• in mhm_driver.f90:

  • the pointer eval should be of type eval_interface from mo_optimization_utils

    https://git.ufz.de/mhm/mhm/-/blob/develop/src/mHM/mhm_driver.f90#L172

  • the pointer obj_func should be of type objective_interface from mo_optimization_utils

    https://git.ufz.de/mhm/mhm/-/blob/develop/src/mHM/mhm_driver.f90#L173

• in https://git.ufz.de/mhm/mhm/-/blob/develop/src/common/mo_read_latlon.f90#L106, an error occures:

  0: SHAPE: arg not associated with array

  (very descriptive) ... my educated guess is, that PGI has a problem with the generic procedures in mo_netcdf (https://git.ufz.de/mhm/mhm/-/blob/develop/src/common/mo_read_latlon.f90#L106)

• there are a lot of pre-processor directives across the code-base to handle PGI-Fortran compilation. We would need to test, which of these are still necessary and if we would need more of them to handle problems like the one described above (what a mess)

• is it worth the hassle?

List TBC...