Fix Syslog::Logger logs

Send logs further if logdev not defined.

Author: alex-slynko

lib/active_record/session_store/extension/logger_silencer.rb

@@ -30,7 +30,7 @@ def level_with_threadsafety
         end
 
         def add_with_threadsafety(severity, message = nil, progname = nil, &block)
-          if !defined?(@logdev) || @logdev.nil? || (severity || UNKNOWN) < level
+          if (defined?(@logdev) && @logdev.nil?) || (severity || UNKNOWN) < level
             true
           else
             add_without_threadsafety(severity, message, progname, &block)