Improve error handling in scePsmfPlayerStart().
Add support for initPts in scePsmfPlayerStart().

It won't be super speedy though, could more ideally do it on the calls to
Update()...
scePsmfPlayerStart() can also rewind.
Validate and support stream params in psmfplayer.
When psmfplayer video is behind audio, skip frames.

This is what the PSP does.  Basically the audio pts drives sync.
Fix ranged mpeg memchecks, oops.
Merge pull request #6073 from unknownbrackets/psmfplayer

Cleanup psmfplayer pts/frame/audio sync, handle start parameters