ALSA: oxfw: allow PCM capture for Stanton SCS.1m

ALSA: oxfw: allow PCM capture for Stanton SCS.1m

commit d8fa87c368f5b4096c4746894fdcc195da285df1 upstream.

Stanton SCS.1m can transfer isochronous packet with Multi Bit Linear
Audio data channels, therefore it allows software to capture PCM
substream. However, ALSA oxfw driver doesn't.

This commit changes the driver to add one PCM substream for capture
direction.

Fixes: de5126cc3c0b ("ALSA: oxfw: add stream format quirk for SCS.1 models")
Cc: <stable@vger.kernel.org> # v4.5+
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>