[ALSA] oxygen: make SPI/2-wire configuration model-specific

Allow the model drivers to specify if the codec communication goes over
SPI or a 2-wire bus.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/pci/oxygen/hifier.c b/sound/pci/oxygen/hifier.c
index fa489ed..143d83d 100644
--- a/sound/pci/oxygen/hifier.c
+++ b/sound/pci/oxygen/hifier.c
@@ -164,7 +164,7 @@
 		       PLAYBACK_1_TO_SPDIF |
 		       CAPTURE_0_FROM_I2S_1,
 	.dac_channels = 2,
-	.function_flags = 0,
+	.function_flags = OXYGEN_FUNCTION_SPI,
 	.dac_i2s_format = OXYGEN_I2S_FORMAT_LJUST,
 	.adc_i2s_format = OXYGEN_I2S_FORMAT_LJUST,
 };