Merge branch 'dsa-headroom'

Per Forlin says:

====================
net: dsa: Make sure there is headroom for tag

Sorry for re-posting yet another time....
I manage to include multiple email-senders and forgot to include cover-letter.
Let's hope everyhthing is in order this time.

Fix two tag drivers to make sure there is headroom for the tag data.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

net/dsa/tag_ar9331.c

@@ -31,7 +31,7 @@ static struct sk_buff *ar9331_tag_xmit(struct sk_buff *skb,
 	__le16 *phdr;
 	u16 hdr;
 
-	if (skb_cow_head(skb, 0) < 0)
+	if (skb_cow_head(skb, AR9331_HDR_LEN) < 0)
 		return NULL;
 
 	phdr = skb_push(skb, AR9331_HDR_LEN);

net/dsa/tag_qca.c

@@ -33,7 +33,7 @@ static struct sk_buff *qca_tag_xmit(struct sk_buff *skb, struct net_device *dev)
 	struct dsa_port *dp = dsa_slave_to_port(dev);
 	u16 *phdr, hdr;
 
-	if (skb_cow_head(skb, 0) < 0)
+	if (skb_cow_head(skb, QCA_HDR_LEN) < 0)
 		return NULL;
 
 	skb_push(skb, QCA_HDR_LEN);