Don't build the New Fortran Goodness (NFG) when the compiler doesn't support C_FUNLOC properly

Original patch from @ggouaillardet; slight wording tweak by @jsquyres.

This patch is reviewed and ready to go.  It fixes an issue that Siegmar has raised on the mailing list about recent versions of the Oracle Fortran compiler.

Cherry picked from master:
* open-mpi/ompi@27aec2e - original @ggouaillardet commit
* open-mpi/ompi@e5b0b81 - working tweak from @jsquyres