Revert "Hide the correct widget (minicanvas) when patchbay is hidden"

This reverts commit 515c227e06.

source/frontend/carla_host.py

@@ -281,7 +281,7 @@ class HostWindow(QMainWindow):
             self.ui.menu_Canvas.setEnabled(False)
             self.ui.menu_Canvas.setVisible(False)
             self.ui.menu_Canvas.menuAction().setVisible(False)
-            self.ui.tw_miniCanvas.hide()
+            self.ui.miniCanvasPreview.hide()
             self.ui.tabWidget.removeTab(1)
             if WINDOWS:
                 self.ui.tabWidget.tabBar().hide()