Set the audio/video streams per sceMpegGet*Au()

This fixes #2226, thanks to @raven02 for finding the issue.  Could also help e.g. Xyanide: Resurrection (which also reports invalid video stream) and a few other games.

The video codec change path is not super well tested, because I couldn't find a game that triggered it, but it should work.

Alternative to #4987.

-[Unknown]