rsyslog-config: fix disabled config

When no remote syslog is used action ~ (drop) isn't appropriate as it
inhibits processing of the current message for any additional configs
that might come after server.conf. This file shouldn't be empty either
as there're no other output actions defined in default configuration.

Make it a no-op by sending to /dev/null instead. Add a linefeed at the
end so that "cat server.conf" would look nicer.

Signed-off-by: Paul Fertser <fercerpav@gmail.com>
Change-Id: I6636c76cf0304b3c36f579225846ab19e992c333
diff --git a/phosphor-rsyslog-config/server-conf.cpp b/phosphor-rsyslog-config/server-conf.cpp
index fb5d086..ad12a9e 100644
--- a/phosphor-rsyslog-config/server-conf.cpp
+++ b/phosphor-rsyslog-config/server-conf.cpp
@@ -187,10 +187,12 @@
     }
     else // this is a disable request
     {
-        // write '*.* ~' - this causes rsyslog to discard all messages
-        stream << "*.* ~";
+        // dummy action to avoid error 2103 on startup
+        stream << "*.* /dev/null";
     }
 
+    stream << std::endl;
+
     restart();
 }