dm9601: Fix receive MTU

dm9601 didn't take the ethernet header into account when calculating
RX MTU, causing packets bigger than 1486 to fail.

Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/net/usb/dm9601.c b/drivers/net/usb/dm9601.c
index 16c7a0e..a2de32f 100644
--- a/drivers/net/usb/dm9601.c
+++ b/drivers/net/usb/dm9601.c
@@ -405,7 +405,7 @@
 	dev->net->ethtool_ops = &dm9601_ethtool_ops;
 	dev->net->hard_header_len += DM_TX_OVERHEAD;
 	dev->hard_mtu = dev->net->mtu + dev->net->hard_header_len;
-	dev->rx_urb_size = dev->net->mtu + DM_RX_OVERHEAD;
+	dev->rx_urb_size = dev->net->mtu + ETH_HLEN + DM_RX_OVERHEAD;
 
 	dev->mii.dev = dev->net;
 	dev->mii.mdio_read = dm9601_mdio_read;