Build errors on develop branch with OpenMP Enabled

[rcarson3]

I'm currently testing CARE out on an linux machine with GCC v7.5.0 compiler suite and a toss3 machine with GCC v7.3.0.

I'm finding that the build is failing on the TestSortFuser example with a number of errors that appear related to the RAJA execution policy for example here's one of the hard errors:

CARE/src/care/SortFuser.h:265:25: error: no matching function for call to ‘sortArray(RAJA::PolicyBaseT<(RAJA::Policy)4, (RAJA::Pattern)1, (RAJA::Launch)0, (camp::resources::v1::Platform)1, RAJA::policy::omp::Parallel, RAJA::wrapper<RAJA::policy::omp::omp_for_schedule_exec<RAJA::policy::omp::Auto> > >, care::host_device_ptr<int>&, int&)’
          care::sortArray(RAJAExec{}, m_concatenated_result, m_total_length);

It should be pretty easy to reproduce on an LC machine with the following cmake invocation on commit 654b9fa:

cmake ../ -DENABLE_OPENMP=ON -DCMAKE_INSTALL_PREFIX=../install_dir/