Audio MOAC II: AC97 edition

[richardg867]

The AC97 Audio Stuff

• Add AC97 audio codec emulation (all codecs support the variable sample rate feature regardless of what they identify as)
• Add emulated AC97 codec to ES1371 (still identifies as a CS4297A codec like VMware; TriTech, Asahi Kasei and Creative codecs were more common, but at least one real ES1373 card used the CS4297A)
• Add missing I/O port operation fallbacks to ES1371, closes #595
• Add VIA 686A/B AC97 audio controller (FIC VA-503A and Acorp 6VIA90AP have on-board codecs which are always enabled; ASUS CUV4X-LS has the option of adding a fictional AMR card with CS4297A codec)
• Add VIA 686A/B Sound Blaster emulation (currently #defined to a real OPL3 instance as the stuff used by the viafmtsr emulator is poorly documented)
• Switch FIC VA-503A to the audio-enabled BIOS

The Other Stuff

• Add actual PnP ROM dumps to Sound Blasters (except 16), closes #1578
• Add IDE controller to PnP Sound Blasters (claims tertiary channel)
• Extend CS423x RAM to a full 64k (did not fix control register device on VXD driver)
• Improve VIA 686 Super I/O and hardware monitor to match probed hardware behavior (mostly undefined port stuff)
• Change internal name for enhanced Am486 (with config migration path)
• Fix some entries in the legacy CPU table conversion code to match renamed machines

[Ompronce]

Thanks for implementing the SB PnP changes I suggested and more.

Would it be possible to allow users to choose either the CT3980 or the CT3990 PnP EEPROMs, as well as the choice of the CT4390 or CT4540 PnP EEPROMs? (similar to the alternate ROM file checks seen on some machines).