ALSA: usb-audio: add support for Native Instruments MK2 devices

The MK2 generation of Native Instruments' sound cards are in fact
compliant to the USB audio standard of version 2 and other approved USB
standards. However, they come up as vendor-specific device when first
connected but can be told to come up with a new set of descriptors
upon their next enumeration. The interfaces announced by the new
descriptors will be handled by the kernel's class drivers. This is done
by issuing a vendor specific device request and sending the device to
reset.

There are also some vendor-specific USB requests for some mixer elements
that can't be exported in a standard compliant way. The driver now
supports them with quirks handling mechanisms.

Signed-off-by: Daniel Mack <daniel@caiaq.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/usb/quirks-table.h

@@ -2283,6 +2283,20 @@ YAMAHA_DEVICE(0x7010, "UB99"),
 	}
 },
 
+/* Native Instruments MK2 series */
+{
+	/* Traktor Audio 6 */
+	.match_flags = USB_DEVICE_ID_MATCH_DEVICE,
+	.idVendor = 0x17cc,
+	.idProduct = 0x1010,
+},
+{
+	/* Traktor Audio 10 */
+	.match_flags = USB_DEVICE_ID_MATCH_DEVICE,
+	.idVendor = 0x17cc,
+	.idProduct = 0x1020,
+},
+
 /* Miditech devices */
 {
 	USB_DEVICE(0x4752, 0x0011),