Sound driver comments and corrections

I equated some unequated a6 references.
Pointed out a bug or two.
Added some comments.
Corrected/expanded some comments and labels.
Pointed out some redundancies and how to be rid of them.
Merge pull request #1 from Clownacy/master

Sound driver comments and corrections
Added Hivebrain labels

I found myself doing this for the second time, so I decided to make it
the last.

I also renamed Snd_FadeOutSFX and Snd_FadeOutSFX2. The Snd prefix is
unnecessary and clashes with similar code's labels, and SFX2 focuses on
Special SFXes.

Also added cfSetCommunication's previous label.
Merge pull request #2 from Clownacy/master

Added Hivebrain labels
Sync with master