[ALSA] usb-audio: add Roland RD-700SX support

USB generic driver
Add a quirk entry for the Roland RD-700SX.
This should work for the RD-300SX, too.
Signed-off-by: NClemens Ladisch <clemens@ladisch.de>

sound/usb/usbquirks.h

@@ -1010,6 +1010,19 @@ YAMAHA_DEVICE(0x7010, "UB99"),
 		}
 	}
 },
+{
+	USB_DEVICE_VENDOR_SPEC(0x0582, 0x007a),
+	.driver_info = (unsigned long) & (const snd_usb_audio_quirk_t) {
+		.vendor_name = "Roland",
+		/* RD-700SX, RD-300SX */
+		.ifnum = 0,
+		.type = QUIRK_MIDI_FIXED_ENDPOINT,
+		.data = & (const snd_usb_midi_endpoint_info_t) {
+			.out_cables = 0x0003,
+			.in_cables  = 0x0003
+		}
+	}
+},
 
 /* Midiman/M-Audio devices */
 {