ALSA: usb-audio - Add "cval->res = 384" quirk for Logitech Webcam C600

One more affected devices: Logitech Webcam C600 (046d:0808)

Volume range before quirk is 6400, after (also real) is 16.
Signed-off-by: Alexey Fisher <bug-track@fisher-privat.net>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/usb/mixer.c

@@ -1122,6 +1122,7 @@ static void build_feature_ctl(struct mixer_build *state, void *raw_desc,
 		}
 		break;
 
+	case USB_ID(0x046d, 0x0808):
 	case USB_ID(0x046d, 0x0809):
 	case USB_ID(0x046d, 0x0991):
 	/* Most audio usb devices lie about volume resolution.