This PR makes a few changes to Save States to allow single-instance Runahead to work properly:
Adds the TIA and POKEY chip variables to the state, which fixes distorted audio in single-instance runahead mode
Adds the BIOS portion of the RAM to the state, which fixes issues with many games freezing when transitioning from the BIOS to the actual game with runahead enabled
Uses the RETRO_ENVIRONMENT_GET_AUDIO_VIDEO_ENABLE callback to only apply the above changes to the state when runahead single-instance is enabled, so existing and "normal" save states will still be the same size/format as before
This PR makes a few changes to Save States to allow single-instance Runahead to work properly: