LOGGING: configure logging from the vty

We can now configure logging to (multiple) files, stderr and syslog
from the vty command line in a persistent way (config file)
diff --git a/src/logging_syslog.c b/src/logging_syslog.c
index b65e819..b558fc0 100644
--- a/src/logging_syslog.c
+++ b/src/logging_syslog.c
@@ -21,6 +21,8 @@
 
 #include "../config.h"
 
+#ifdef HAVE_SYSLOG_H
+
 #include <stdarg.h>
 #include <stdlib.h>
 #include <stdio.h>
@@ -64,9 +66,13 @@
 	if (!target)
 		return NULL;
 
+	target->tgt_syslog.facility = facility;
+	target->type = LOG_TGT_TYPE_SYSLOG;
 	target->output = _syslog_output;
 
 	openlog(ident, option, facility);
 
 	return target;
 }
+
+#endif /* HAVE_SYSLOG_H */