CoreUnpacker: Get rid of no-op call to QtcProcess::terminate()

Calling QtcProcess::terminate() after disconecting from
process signals is a task for implicit ProcessReaper.
Delete the process instead.

Change-Id: I59b0aa1d9df602077d006084635a5321beae0010
Reviewed-by: hjk <hjk@qt.io>

src/plugins/debugger/debuggerruncontrol.cpp

@@ -116,9 +116,6 @@ public:
 private:
     ~CoreUnpacker() final
     {
-        m_coreUnpackProcess.blockSignals(true);
-        m_coreUnpackProcess.terminate();
-        m_coreUnpackProcess.deleteLater();
         if (m_tempCoreFile.isOpen())
             m_tempCoreFile.close();