Replace multiple methods of checking for functions with AC_CHECK_FUNCS
Replace multiple methods of selecting fallback funcs with AC_REPLACE_FUNCS
Replace HAS_* and NEED_* #defines with autogenerated HAVE_*
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Reviewed-by: Adam Jackson <ajax@redhat.com>
Reviewed-by: Mikhail Gusarov <dottedmag@dottedmag.net>
Reviewed-by: Gaetan Nadon <memsize@videotron.ca>
