Debugger: Disconnect LLDB process before destroying the engine

Task-number: QTCREATORBUG-14083
Change-Id: Ic59460dc64b949711fefc82ca137218d3072f7d2
Reviewed-by: Christian Stenger <christian.stenger@theqtcompany.com>
Reviewed-by: hjk <hjk@theqtcompany.com>

src/plugins/debugger/lldb/lldbengine.cpp

@@ -116,6 +116,7 @@ LldbEngine::LldbEngine(const DebuggerStartParameters &startParameters)
 LldbEngine::~LldbEngine()
 {
     m_stubProc.disconnect(); // Avoid spurious state transitions from late exiting stub
+    m_lldbProc.disconnect();
 }
 
 void LldbEngine::executeDebuggerCommand(const QString &command, DebuggerLanguages)