Make sure data.table is linked (not just compiled) with `-fopenmp` in this particular branch of `configure` for Darwin#6633

MichaelChirico merged 1 commit intoRdatatable:masterRdatatable/data.table:masterfrom

dvg-p4:darwin-link-fopenmpdvg-p4/data.table:darwin-link-fopenmpCopy head branch name to clipboard