remove fallback PIDs feature when PMT not found
this was introduced to handle https://github.com/mangui/HLSprovider/issues/71
but the root cause of #71 (PMT not found) was related to bad handling of IV that has been fixed by https://github.com/mangui/HLSprovider/commit/3e29f66404eeb6bc2d6802e370982532c9ed6c99