[ALSA] oxygen: make the number of analog output configurable

Add a field to struct oxygen_model to allow model drivers for cards with
less than eight output channels.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
diff --git a/sound/pci/oxygen/virtuoso.c b/sound/pci/oxygen/virtuoso.c
index 7b240c7..665115d 100644
--- a/sound/pci/oxygen/virtuoso.c
+++ b/sound/pci/oxygen/virtuoso.c
@@ -310,6 +310,7 @@
 	.set_adc_params = set_cs5381_params,
 	.update_dac_volume = update_pcm1796_volume,
 	.update_dac_mute = update_pcm1796_mute,
+	.dac_channels = 8,
 	.used_channels = OXYGEN_CHANNEL_B |
 			 OXYGEN_CHANNEL_C |
 			 OXYGEN_CHANNEL_SPDIF |