Clang: Do not print AliveMessage by default

In 99% of the time this is annoying.

Change-Id: I14749eec6180472221193577aa14b1e396f34ba7
Reviewed-by: David Schulz <david.schulz@qt.io>

src/plugins/clangcodemodel/clangbackendipcintegration.h

@@ -85,6 +85,7 @@ private:
 private:
     AliveHandler m_aliveHandler;
     QHash<quint64, ClangCompletionAssistProcessor *> m_assistProcessorsTable;
+    const bool m_printAliveMessage = false;
 };
 
 class IpcSenderInterface