USB: add speed values for USB 3.0 and wireless controllers

These controllers say "unknown" for their speed in sysfs, which
obviously isn't correct.

Reported-by: Kurt Garloff <[e-mail]>
Cc: Sarah Sharp <[e-mail]>
Cc: David Vrabel <[e-mail]>
Cc: stable <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/usb/core/sysfs.c

···
 	case USB_SPEED_HIGH:
 		speed = "480";
 		break;
+	case USB_SPEED_VARIABLE:
+		speed = "480";
+		break;
+	case USB_SPEED_SUPER:
+		speed = "5000";
+		break;
 	default:
 		speed = "unknown";
 	}