qml: extend the tool tip message of tool bar editor delete profile button

... so that the user knows that deleting all profiles bring back the
default styles (such as default, minimalist, classic styles) with
new profiles.

modules/gui/qt/dialogs/toolbar/qml/ToolbarEditorDialog.qml

@@ -174,7 +174,7 @@ WindowDialog {
                 }
 
                 Widgets.IconToolButton {
-                    description: qsTr("Delete the current profile")
+                    description: qsTr("Delete the current profile.\nDeleting all profiles brings back the default styles.")
                     text: VLCIcons.del
 
                     onClicked: {