ALSA: usb: add UAC3 BADD profiles support

Recently released USB Audio Class 3.0 specification
contains BADD (Basic Audio Device Definition) document
which describes pre-defined UAC3 configurations.

BADD support is mandatory for UAC3 devices, it should be
implemented as a separate USB device configuration.
As per BADD document, class-specific descriptors
shall not be included in the Device’s Configuration
descriptor ("inferred"), but host can guess them
from BADD profile number, number of endpoints and
their max packed sizes.

This patch adds support of all BADD profiles from the spec

Signed-off-by: Ruslan Bilovol <ruslan.bilovol@gmail.com>
Tested-by: Jorge Sanjuan <jorge.sanjuan@codethink.co.uk>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/usb/usbaudio.h

@@ -49,6 +49,8 @@ struct snd_usb_audio {
 	int num_suspended_intf;
 	int sample_rate_read_error;
 
+	int badd_profile;		/* UAC3 BADD profile */
+
 	struct list_head pcm_list;	/* list of pcm streams */
 	struct list_head ep_list;	/* list of audio-related endpoints */
 	int pcm_devs;