[patch] usbnet/smsc75xx: silence uninitialized variable warning

[Dan Carpenter]

If the fn() calls fail then "buf" is uninitialized.  Just return early
in that situation.

Signed-off-by: Dan Carpenter <dan.carpen...@oracle.com>

diff --git a/drivers/net/usb/smsc75xx.c b/drivers/net/usb/smsc75xx.c
index c369db9..9af9799 100644
--- a/drivers/net/usb/smsc75xx.c
+++ b/drivers/net/usb/smsc75xx.c
@@ -99,9 +99,11 @@ static int __must_check __smsc75xx_read_reg(struct usbnet 
*dev, u32 index,
        ret = fn(dev, USB_VENDOR_REQUEST_READ_REGISTER, USB_DIR_IN
                 | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
                 0, index, &buf, 4);
-       if (unlikely(ret < 0))
+       if (unlikely(ret < 0)) {
                netdev_warn(dev->net, "Failed to read reg index 0x%08x: %d\n",
                            index, ret);
+               return ret;
+       }
 
        le32_to_cpus(&buf);
        *data = buf;