[flang][OpenMP] Add `%flang_fc1` `RUN` to delayed privatization tests (#84296)

I did not know how `-mmlir` flag works and was deferring the addition of
`--openm-enabled-delayed-privatization` until later because I thought
some work needs to be done to do that. This commit just adds some extra
`RUN` lines to delayed privatization tests to run them from `flang` as
well.