Fix warning: "Missing emit keyword on signal call"

[-Wclazy-incorrect-emit]

Change-Id: I93bdc6e23cdaccf35c9899ae16870ccc65a54f80
Reviewed-by: Tim Jenssen <tim.jenssen@qt.io>

src/plugins/valgrind/callgrindtool.cpp

@@ -897,7 +897,7 @@ void CallgrindTool::slotRequestDump()
 {
     //setBusy(true);
     m_visualization->setText(tr("Populating..."));
-    dumpRequested();
+    emit dumpRequested();
 }
 
 void CallgrindTool::loadExternalLogFile()