Clean up cmake for Omega on Aurora

[amametjanov]

Move CMAKE_CXX_STANDARD property before cmake project call.

[BFB]

Checklist

• Testing
  • A comment in the PR documents testing used to verify the changes including any tests that are added/modified/impacted.
  • Unit tests have passed. Please provide a relevant CDash build entry for verification.

[amametjanov]

Testing:

• this PR needs
  • Clean up Aurora cmake for Omega E3SM#7357 and
  • merge E3SM master to Omega develop to bring latest Aurora config: Merge E3SM master into Omega develop  #232
• Local CTests after all of the above with oneapi-ifxgpu:

100% tests passed, 0 tests failed out of 31

How-to test on Aurora:

!/bin/bash
cd components/omega/
rm -rf build && mkdir build && cd build
export PARMETIS_ROOT=/home/azamatm/soft/metis

cmake \
   -DOMEGA_CIME_COMPILER=oneapi-ifxgpu \
   -DOMEGA_CIME_MACHINE=aurora \
   -DOMEGA_PARMETIS_ROOT=${PARMETIS_ROOT}\
   -DOMEGA_BUILD_TEST=ON -Wno-dev \
   -S /home/azamatm/repos/Omega/components/omega -B . 2>&1 |tee cmake.1.out

ln -isf /lus/flare/projects/E3SM_Dec/inputdata/ocn/mpas-o/oQU240/ocean.QU.240km.151209.nc test/OmegaMesh.nc
ln -isf /lus/flare/projects/E3SM_Dec/inputdata/ocn/mpas-o/polaris_cache/global_convergence/icos/cosine_bell/Icos480/init/initial_state.230220.nc test/OmegaSphereMesh.nc
ln -isf /lus/flare/projects/E3SM_Dec/inputdata/ocn/mpas-o/polaris_cache/global_convergence/icos/cosine_bell/Icos480/init/PlanarPeriodic48x48.nc test/OmegaPlanarMesh.nc

./omega_build.sh 2>&1 | tee omega_build.sh.1.out

qsub -q debug -l walltime=00:30:00 -A E3SM_Dec -l select=1,filesystems=home:flare -I

cd $PBS_O_WORKDIR
./omega_ctest.sh 2>&1 | tee omega_ctest.sh.1.out