#14416: conditionally add LOG_AUTHPRIV facility and LOG_ODELAY to syslog.

Unlike the other facilities, we don't use a fallback for AUTHPRIV if it
doesn't exist.  Because it is intended for logging sensitive log messages, it
is better that a program trying to log such messages fail than that it log
them insecurely.

Initial patch by Federico Reghenzani.
diff --git a/Doc/library/syslog.rst b/Doc/library/syslog.rst
index 645c326..aa0f5a1 100644
--- a/Doc/library/syslog.rst
+++ b/Doc/library/syslog.rst
@@ -78,12 +78,14 @@
 Facilities:
    :const:`LOG_KERN`, :const:`LOG_USER`, :const:`LOG_MAIL`, :const:`LOG_DAEMON`,
    :const:`LOG_AUTH`, :const:`LOG_LPR`, :const:`LOG_NEWS`, :const:`LOG_UUCP`,
-   :const:`LOG_CRON`, :const:`LOG_SYSLOG` and :const:`LOG_LOCAL0` to
-   :const:`LOG_LOCAL7`.
+   :const:`LOG_CRON`, :const:`LOG_SYSLOG`, :const:`LOG_LOCAL0` to
+   :const:`LOG_LOCAL7`, and, if defined in ``<syslog.h>``,
+   :const:`LOG_AUTHPRIV`.
 
 Log options:
-   :const:`LOG_PID`, :const:`LOG_CONS`, :const:`LOG_NDELAY`, :const:`LOG_NOWAIT`
-   and :const:`LOG_PERROR` if defined in ``<syslog.h>``.
+   :const:`LOG_PID`, :const:`LOG_CONS`, :const:`LOG_NDELAY`, and, if defined
+   in ``<syslog.h>``, :const:`LOG_ODELAY`, :const:`LOG_NOWAIT`, and
+   :const:`LOG_PERROR`.
 
 
 Examples