ALSA: usb-mixer: use defines from audio.h

No need for the private enum.

Signed-off-by: Daniel Mack <daniel@caiaq.de>
Cc: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/usb/usbmixer_maps.c b/sound/usb/usbmixer_maps.c
index 79e903a..d93fc89 100644
--- a/sound/usb/usbmixer_maps.c
+++ b/sound/usb/usbmixer_maps.c
@@ -85,8 +85,8 @@
 	/* 16: MU (w/o controls) */
 	{ 17, NULL, 1 }, /* DISABLED: PU-switch (any effect?) */
 	{ 17, "Channel Routing", 2 },	/* PU: mode select */
-	{ 18, "Tone Control - Bass", USB_FEATURE_BASS }, /* FU */
-	{ 18, "Tone Control - Treble", USB_FEATURE_TREBLE }, /* FU */
+	{ 18, "Tone Control - Bass", UAC_BASS_CONTROL }, /* FU */
+	{ 18, "Tone Control - Treble", UAC_TREBLE_CONTROL }, /* FU */
 	{ 18, "Master Playback" }, /* FU; others */
 	/* 19: OT speaker */
 	/* 20: OT headphone */