qdoc: Change to debug output

Only print debug output if -debug is used
on the command line.

Change-Id: I2bdfca1a072f728427da61f05b34e6e07d933183
Reviewed-by: Jerome Pasion <jerome.pasion@digia.com>

src/tools/qdoc/generator.cpp

@@ -110,7 +110,8 @@ void Generator::setDebugSegfaultFlag(bool b)
  */
 void Generator::debugSegfault(const QString& message)
 {
-    qDebug() << "DEBUG:" << message;
+    if (debugging())
+        qDebug() << "DEBUG:" << message;
 }
 
 /*!