ALSA: usb/6fire: fix repeated words in comments

Delete the redundant word 'in'.

Signed-off-by: wangjianli <wangjianli@cdjrlc.com>
Link: https://lore.kernel.org/r/20220724071644.10630-1-wangjianli@cdjrlc.com


Signed-off-by: Takashi Iwai <tiwai@suse.de>