An allocated memory forgets to be released.
Fixes: 76fdb3a9e1
('ALSA: fireface: add support for Fireface 400')
Cc: <stable@vger.kernel.org> # 4.12+
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>