macosx: do not save resume data if VLC is in private mode

(cherry picked from commit a372720ffe4ebdf05e4145407e611a1cd9f0e72e)
Signed-off-by: Felix Paul Kühne <fkuehne@videolan.org>

modules/gui/macosx/playlist.m

@@ -1562,6 +1562,9 @@
 
 - (void)storePlaybackPositionForItem:(input_thread_t *)p_input_thread
 {
+    if (!var_InheritBool(VLCIntf, "macosx-recentitems"))
+        return;
+
     input_item_t *p_item = input_GetItem(p_input_thread);
     if (!p_item)
         return;