[tree, fortran] Patch: make --enable-mapped-location build

[François-Xavier Coudert]

(Thanks Andrew for CCing!)

> Index: fortran/ChangeLog
> from  Tom Tromey  <tromey@redhat.com>
>
>         * scanner.c (gfc_next_char_literal): Use gfc_linebuf_linenum.
>         * gfortran.h (gfc_linebuf_linenum): New macro.

The Fortran part is OK.