Update fabm0d's gotm interface

[ruiying-ocean]

The fabm0d.F90 in this repo failed to compile when I followed this instruction (https://github.com/fabm-model/fabm/wiki/0D-driver).
The error comes from the outdated utils in GOTM, which uses a density module

   17 |    use eqstate,only:rho_feistel
      |        1
Fatal Error: Cannot open module file 'eqstate.mod' for reading at (1): No such file or directory
compilation terminated.
gmake[2]: *** [CMakeFiles/fabm0d.dir/build.make:91: CMakeFiles/fabm0d.dir/fabm0d.F90.o] Error 1
gmake[1]: *** [CMakeFiles/Makefile2:991: CMakeFiles/fabm0d.dir/all] Error 2
gmake: *** [Makefile:136: all] Error 2

updating it to use density,only:get_rho resolves the bug.

[bolding]

Hi

The development of GOTM is done in a devel branch and releases are in the stable branch. One of the new developments is the switch to TEOS-10 for density related routines. This implies a new interface that has not been adapted to fabm0d yet.

Karsten

[jornbr]

And that's why the box model instructions state you'll need the latest stable GOTM. :-) As soon as the current developers' version of GOTM is released as stable, we will update FABM's box model to use it. We'll leave your pull request open here for that purpose - thanks.

[ruiying-ocean]

Thanks both! I didn't notice that I was using development version of gotm. That explains it all.