sky2: checksum offload plus vlan bug

Driver was not correctly setting up transmit descriptor when doing
VLAN tag insertion with checksum offload.

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/net/sky2.c b/drivers/net/sky2.c
index d9bc98b..7d94eab 100644
--- a/drivers/net/sky2.c
+++ b/drivers/net/sky2.c
@@ -1432,7 +1432,7 @@
 		tcpsum = offset << 16;		/* sum start */
 		tcpsum |= offset + skb->csum_offset;	/* sum write */
 
-		ctrl = CALSUM | WR_SUM | INIT_SUM | LOCK_SUM;
+		ctrl |= CALSUM | WR_SUM | INIT_SUM | LOCK_SUM;
 		if (ip_hdr(skb)->protocol == IPPROTO_UDP)
 			ctrl |= UDPTCP;