Resurrect ports depending on devel/openmp.
These ports will transition transparantly to openmp from base once
FreeBSD 12.0 reaches end-of-life.
Reported by: jbeich [1] [2]
[1] https://lists.freebsd.org/pipermail/svn-ports-head/2019-May/210482.html
[2] https://lists.freebsd.org/pipermail/svn-ports-head/2019-December/229648.html