CdbEngine: Remove unused field

This field in only set, but never read.

Change-Id: Ie42ccad32ca90e1b4a0dd9f4c2e213ea4c3ca180
Reviewed-by: <github-actions-qt-creator@cristianadam.eu>
Reviewed-by: David Schulz <david.schulz@qt.io>

src/plugins/debugger/cdb/cdbengine.cpp

@@ -225,7 +225,6 @@ void CdbEngine::init()
     m_hasDebuggee = false;
     m_sourceStepInto = false;
     m_watchPointX = m_watchPointY = 0;
-    m_ignoreCdbOutput = false;
     m_autoBreakPointCorrection = false;
     m_wow64State = wow64Uninitialized;
 
@@ -670,8 +669,9 @@ void CdbEngine::shutdownEngine()
         return;
     }
 
-    // No longer trigger anything from messages
-    m_ignoreCdbOutput = true;
+    m_process.setStdOutCallback({});
+    m_process.setStdErrCallback({});
+
     // Go for kill if there are commands pending.
     if (m_accessible && !commandsPending()) {
         // detach (except console): Wait for debugger to finish.

src/plugins/debugger/cdb/cdbengine.h

@@ -221,7 +221,6 @@ private:
     QSet<Breakpoint> m_pendingBreakpointMap;
     bool m_autoBreakPointCorrection = false;
     QMultiHash<QString, quint64> m_symbolAddressCache;
-    bool m_ignoreCdbOutput = false;
     QList<InterruptCallback> m_interrupCallbacks;
     QList<SourcePathMapping> m_sourcePathMappings;
     QScopedPointer<GdbMi> m_coreStopReason;