Enable OpenMP also for macosx

added BugFix Build System Reconstruction labels

Dear @f.uhlig, @v.friese, @p.-a.loizeau, @se.gorbunov, @v.akishina,

you have been identified as code owner of at least one file which was changed with this merge request.

Please check the changes and approve them or request changes.

added CodeOwners label

approved this merge request

merged