[flang] [clang] [flang][driver] Add -fno-fortran-main (link time) option to remove Fortran_main from link line (PR #74139)

[Tom Eccles via cfe-commits]

https://github.com/tblah approved this pull request.

Thanks for the fix. LGTM

https://github.com/llvm/llvm-project/pull/74139