ALSA: firewire-motu: fix error return code in snd_motu_stream_reserve_duplex()

Fix to return a negative error code from the error handling
case instead of 0, as done elsewhere in this function.

Fixes: e50dfac8 ("ALSA: firewire-motu: cache event ticks in source packet header per data block")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Acked-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20210603143203.582017-1-yangyingliang@huawei.com


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