omega-h: update to versions 9.19.0, 9.19.1 (#9548)
omega-h: update to versions 9.19.0, 9.19.1 (#9548)

* omega-h: update to versions 9.19.0, 9.19.1

* omega-h: add build conflict for gcc-8

iulian787/spack,iulian787/spack,LLNL/spack,iulian787/spack,LLNL/spack,LLNL/spack,LLNL/spack,LLNL/spack,iulian787/spack,iulian787/spack