Corrects "application/octet-stream is for arbitrary binary files"

[poeplva]

1321 had a syntax error, this commit corrects it.

[2084x]

might be worth adding a line for transport streams as well:

ts) setsid -f mpv $f -quiet >/dev/null 2>&1 ;;

for some reason they are recognised as application/octet-stream instead of video/mp2t