clear the placeholder label

src/plugins/perforce/settingspage.cpp

@@ -46,6 +46,7 @@ SettingsPageWidget::SettingsPageWidget(QWidget *parent) :
     QWidget(parent)
 {
     m_ui.setupUi(this);
+    m_ui.errorLabel->clear();
     m_ui.pathChooser->setPromptDialogTitle(tr("Perforce Command"));
     m_ui.pathChooser->setExpectedKind(PathChooser::Command);
     connect(m_ui.testPushButton, SIGNAL(clicked()), this, SLOT(slotTest()));