Summary

This PR implements EGA/VGA/SVGA VSync interrupts for ISA/VLB/MCA cards.

VGA/SVGA VSync interrupts can be disabled by configuration. EGA VSync interrupts are controlled entirely by software.

Checklist

• I have tested my changes locally and validated that the functionality works as intended
• 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/
• This pull request requires changes to the asset set
  • I have opened an assets pull request - https://github.com/86Box/assets/pull/changeme/

References

None.