Summary

Add the Yamaha YMF-701 (OPL3-SA) audio controller and give the Intel TC430HX and AG430HX (Vaio PCV-90) their onboard YMF-701 audio. Also add an implementation of the CS423x timer interrupt as the 1997 Windows NT drivers require this to detect available IRQs.

Known issues:

• The Yamaha SoftSynth included with the Windows 3.1x and 9x VxD drivers doesn't work on drivers newer than July 1996 (The November and December 1996 drivers and any drivers from 1997 output silence while the Win9x April 1999 drivers throw a MMSYSTEM001 when the SoftSynth MIDI device is selected and MIDI playback is attempted.) I have not been able to find the cause of this.
• When using the ISA card version of this the Windows 9x drivers will not detect the card (the onboard one autodetects without issue.) This occurs on real hardware and has a workaround: https://www.vogons.org/viewtopic.php?t=100527

Checklist

• Closes #xxx
• I have discussed this with core contributors already
• This pull request requires changes to the ROM set
  • I have opened a roms pull request - https://github.com/86Box/roms/pull/changeme/

References

Provide links to datasheets or other documentation that helped you implement this pull request.

• Crystal CS4231A datasheet: https://theretroweb.com/chip/documentation/cs4231a-660aef84ede23491542853.pdf
• Linux YMF-701 driver: https://deerpond.whoi.edu/dgiaya/linux/-/blob/v2.6.18-rc6/sound/oss/opl3sa.c
• Intel TC430HX Technical Specification: https://theretroweb.com/motherboard/manual/tc430hx-5f0789db1ea28542405826.pdf
• Intel AG430HX Technical Specification: https://theretroweb.com/motherboard/manual/manual-motherboard-intel-ag430hx-motherboard-28183301-5f2f11cfdfb5e378734554.pdf