[ALSA] usbusx2yaudio: kfree(NULL) is valid

if (!x) kfree(x); is not needed since kfree(NULL) is valid.

Signed-off-by: Richard Knutsson <ricknu-0@student.ltu.se>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>
1 file changed