bnx2x: fix UDP checksum for 57710/57711.

Since commit 86564c3f "bnx2x: Remove many sparse warnings" UDP
csum offload is broken for 57710/57711. Fix return value.

Signed-off-by: Dmitry Kravkov <dmitry@broadcom.com>
CC: Ariel Elior <ariele@broadcom.com>
CC: Yuval Mintz <yuvalmin@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c
index ecac04a3..a923bc4 100644
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c
@@ -3142,7 +3142,7 @@
 		tsum = ~csum_fold(csum_add((__force __wsum) csum,
 				  csum_partial(t_header, -fix, 0)));
 
-	return bswab16(csum);
+	return bswab16(tsum);
 }
 
 static inline u32 bnx2x_xmit_type(struct bnx2x *bp, struct sk_buff *skb)