Remove ISA sound cards from NOTES

Fixes: df51e63eb5d7 ("Retire snd_ad1816 ISA sound card driver")
Fixes: aa83e9b189d6 ("Retire snd_ess ISA sound card driver")
Fixes: 754decef384a ("Retire snd_gusc ISA sound card driver")
Fixes: 5126e5eeeb5e ("Retire snd_mss ISA sound card driver")
Fixes: 716924cb4832 ("Retire snd_sbc ISA sound card driver")

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