ALSA: line6: Only determine control port properties if needed

Not all line6 devices use the control port.
Signed-off-by: NAndrej Krutak <dev@andree.sk>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

sound/usb/line6/driver.c

@@ -612,9 +612,8 @@ int line6_probe(struct usb_interface *interface,
 		goto error;
 	}
 
-	line6_get_interval(line6);
-
 	if (properties->capabilities & LINE6_CAP_CONTROL) {
+		line6_get_interval(line6);
 		ret = line6_init_cap_control(line6);
 		if (ret < 0)
 			goto error;