Add deprecation notices to ISA sound cards

[emaste]

Summary

ISA sound cards are long obsolete. Add deprecation notices to device attach routines and man pages for:

snd_ad1816  Analog Devices AD1816 SoundPort
snd_ess     Ensoniq ESS
snd_gusc    Gravis UltraSound
snd_mss     Microsoft Sound System
snd_sbc     Creative Sound Blaster

(Will bump .Dd prior to commit)

[mav]

I don't have specific objections except nostalgic. I was thinking about it from perspective of Giant lock many of them use. There are few Giant-locked PCI sound drivers too, but that may go separately: either fix or also remove.

[emaste]

https://lists.freebsd.org/archives/freebsd-current/2022-March/001680.html
https://lists.freebsd.org/archives/freebsd-stable/2022-March/000585.html