In error path of snd_dice_stream_init_duplex(), stream data for incoming
packet can be left to be initialized.

This commit fixes it.

Fixes: 436b5abe ('ALSA: dice: handle whole available isochronous streams')
Cc: <stable@vger.kernel.org> # v4.6+
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>