The comment in UAC2 clock selector descriptor definition mentions the
bAssocTerminal after baCSourceID[], but it doesn't exist in the actual
definition.  Let's correct it.

Fixes: 5dd360eb ("include/linux/usb/audio-v2.h: add more UAC2 details")
Signed-off-by: NTakashi Iwai <tiwai@suse.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>