staging/usbip: simplify usbip_dump_usb_device() udev->speed handling

Change usbip_dump_usb_device() to use usb_speed_string() and remove the
code that does switch on udev->speed and builds custom speed strings.

Signed-off-by: Shuah Khan <shuah.kh@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/staging/usbip/usbip_common.c b/drivers/staging/usbip/usbip_common.c
index 96552e3..4a2aab1 100644
--- a/drivers/staging/usbip/usbip_common.c
+++ b/drivers/staging/usbip/usbip_common.c
@@ -99,26 +99,8 @@
 	struct device *dev = &udev->dev;
 	int i;
 
-	dev_dbg(dev, "       devnum(%d) devpath(%s) ",
-		udev->devnum, udev->devpath);
-
-	switch (udev->speed) {
-	case USB_SPEED_HIGH:
-		pr_debug("SPD_HIGH ");
-		break;
-	case USB_SPEED_FULL:
-		pr_debug("SPD_FULL ");
-		break;
-	case USB_SPEED_LOW:
-		pr_debug("SPD_LOW ");
-		break;
-	case USB_SPEED_UNKNOWN:
-		pr_debug("SPD_UNKNOWN ");
-		break;
-	default:
-		pr_debug("SPD_ERROR ");
-		break;
-	}
+	dev_dbg(dev, "       devnum(%d) devpath(%s) usb speed(%s)",
+		udev->devnum, udev->devpath, usb_speed_string(udev->speed));
 
 	pr_debug("tt %p, ttport %d\n", udev->tt, udev->ttport);