interface: don't implement a set_tile callback for the vout_window_t

Fixes warnings in C++.

modules/gui/minimal_macosx/intf.m

@@ -188,6 +188,7 @@ static const struct vout_window_operations ops = {
     WindowSetState,
     WindowUnsetFullscreen,
     WindowSetFullscreen,
+    NULL,
 };
 
 int WindowOpen(vout_window_t *p_wnd)

modules/gui/qt/main_interface.cpp

@@ -735,6 +735,7 @@ bool MainInterface::getVideo( struct vout_window_t *p_wnd )
         MainInterface::requestVideoState,
         MainInterface::requestVideoWindowed,
         MainInterface::requestVideoFullScreen,
+        NULL,
     };
 
     if( videoActive.test_and_set() )

modules/gui/skins2/src/skin_main.cpp

@@ -434,6 +434,7 @@ static const struct vout_window_operations window_ops = {
     WindowSetState,
     WindowUnsetFullscreen,
     WindowSetFullscreen,
+    NULL,
 };
 
 static int WindowOpen( vout_window_t *pWnd )