ALSA: usb-midi: correct speed checking

Allow for SS+ USB devices

Signed-off-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/usb/midi.c b/sound/usb/midi.c
index 47de8af..7ba9292 100644
--- a/sound/usb/midi.c
+++ b/sound/usb/midi.c
@@ -911,6 +911,7 @@
 	switch (snd_usb_get_speed(ep->umidi->dev)) {
 	case USB_SPEED_HIGH:
 	case USB_SPEED_SUPER:
+	case USB_SPEED_SUPER_PLUS:
 		count = 1;
 		break;
 	default: