Log Message:
libopenmpt: update to 0.5.10.

### libopenmpt 0.5.10 (2021-07-04)

 *  S3M: Honor the Stereo flag not being set. This improves the sound of some
    tunes like Turbulence by Purple Motion.
 *  S3M: Detect MPT 1.0 alpha versions which didn't set the Stereo flag. In this
    case, the unset Stereo flag is also ignored because MPT 1.0 alpha used the
    default S3M channel panning anyway.
 *  S3M: Only for OPL instruments the high sample rate bits should be ignored;
    for PCM instruments they are clamped to 65535 Hz.
 *  MOD: Do not apply ProTracker loop length quirk to MODs that could have been
    made with Scream Tracker (fixes Soul-O-Matic by Purple Motion).
 *  AMF (DSMI): Format revisions 1 and 9, as well as early (technically
    malformed) revision 10 files, are now supported. Surround panning commands
    and instrument number without note are now converted correctly.
 *  AMF (DSMI): Patterns and samples were not read correctly in some files
    (e.g. AVOID.AMF).
 *  GDM: Correctly import extra-fine portamentos.

 *  mpg123: Update to v1.28.0 (2021-06-05).
 *  ogg: Update to v1.3.5 (2021-06-04).
 *  stb_vorbis: Update v1.21 commit 8e51be04dc7dcee462e1f09e410faceab52cc6d2
    (2021-07-02).