A Solaris system header has a #define for "sun". This renames
that variable to avoid the conflict, fixing a build error with
--enable-targets=all on Solaris.
gdb/ChangeLog:
2019-12-19 Christian Biesinger <cbiesinger@google.com>
* fbsd-tdep.c (fbsd_info_proc_files_entry): Rename local var
"sun" to "saddr_un".