No cdo version check

I discovered some problems with cdo 1.9.6 on mistral. Chris had written a fix to match the versions of gcc and cdo, which for mysterious reasons where mismatched on mistral a while ago. However, since cdo 1.9.6 appears to be broken; the version check part of esm-environment just hangs. For example, when trying to compile fesom-2.0:

a270077@mlogin108% make comp-fesom-2.0
module purge; cd esm-environment; source ./esm-env.sh intelmpi; cd ../fesom-2.0;  mkdir build -p; cd build; cmake ..;  make install -j `nproc --all`
======== esm-environment/mistral.dkrz.de: ========
   Load eventually missing shared library dependencies for cdo with LD_LIBRARY_PATH ...
   LD_LIBRARY_PATH: /sw/rhel6-x64/intel/intel-18.0.4/mkl/lib/intel64:/sw/rhel6-x64/intel/intel-18.0.4/lib/intel64:/sw/rhel6-x64/grib_api/grib_api-1.15.0-intel14/lib:
      execute 'strings -a /sw/rhel6-x64/cdo/cdo-1.9.6-magicsxx-gcc64/bin/cdo | grep 'GCC: (' ...
make: *** [comp-fesom-2.0] Error 1

Taking out the version check allows for a successful compilation; but I am sure there were good reasons to have this check in there. @a270058 or @a270089; can you make an executive decision?