ALSA: oxfw: fix to handle correct stream for PCM playback

When userspace application calls ioctl(2) to configure hardware for PCM
playback substream, ALSA OXFW driver handles incoming AMDTP stream.
In this case, outgoing AMDTP stream should be handled.

This commit fixes the bug for v5.3-rc kernel.

Fixes: 4f380d00 ("ALSA: oxfw: configure packet format in pcm.hw_params callback")
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>