Massive sound changes / fix (24/32bit pcm support, new sampling rate converter, various fixes)

[Michael Seyfert]

> General sound infrastructure changes
> ====================================
> 
> ac97.c
>    * Slightly new method to detect mixer capabilities and resolution.
>      This mostly to help CT4730, but apparently it does help other
>      cards too (especially via8233x). This probably need futher test
>      and confirmation from other people with ac97 cards other than via
>      / es137x.
>    * Aggresive dac power wake up call, again, to help CT4730 (and
>      probably others).


Please revert src/sys/dev/sound/pcm/ac97.c back to 1.43, these changes mess up the volume control on my
audigy 2 card. It seems the struct ac97mixtable_entry.bits field isn't getting properly
setup.

I'm not sure what you're doing with this code:

for (k = 0; j != 0; k++)
	j >>= 1;
for (j = 0; k != 0; j++)
	k >>= 1;
if (j != 0) {
	codec->mix[i].enable = 1;
#if 0
	codec->mix[i].bits = j;
#endif
} else
	codec->mix[i].enable = 0;