Remove unused QObject parent arguments on options pages

In the new plugin setup scheme they are data members of the
plugin pimpl and never use the parent.

Change-Id: I28fe150393e8159064dcfbd113ce0320af50fd58
Reviewed-by: Eike Ziller <eike.ziller@qt.io>

src/plugins/autotest/qtest/qttestsettingspage.cpp

@@ -35,8 +35,7 @@
 namespace Autotest {
 namespace Internal {
 
-QtTestSettingsWidget::QtTestSettingsWidget(QWidget *parent)
-    : QWidget(parent)
+QtTestSettingsWidget::QtTestSettingsWidget()
 {
     m_ui.setupUi(this);
     m_ui.callgrindRB->setEnabled(Utils::HostOsInfo::isAnyUnixHost()); // valgrind available on UNIX