r8152: replace get_protocol with vlan_get_protocol

vlan_get_protocol() has been defined and use it to replace
get_protocol().

Signed-off-by: Hayes Wang <hayeswang@realtek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/usb/r8152.c

@@ -1330,18 +1330,6 @@ static struct tx_agg *r8152_get_tx_agg(struct r8152 *tp)
 	return agg;
 }
 
-static inline __be16 get_protocol(struct sk_buff *skb)
-{
-	__be16 protocol;
-
-	if (skb->protocol == htons(ETH_P_8021Q))
-		protocol = vlan_eth_hdr(skb)->h_vlan_encapsulated_proto;
-	else
-		protocol = skb->protocol;
-
-	return protocol;
-}
-
 /* r8152_csum_workaround()
  * The hw limites the value the transport offset. When the offset is out of the
  * range, calculate the checksum by sw.
@@ -1447,7 +1435,7 @@ static int r8152_tx_csum(struct r8152 *tp, struct tx_desc *desc,
 			goto unavailable;
 		}
 
-		switch (get_protocol(skb)) {
+		switch (vlan_get_protocol(skb)) {
 		case htons(ETH_P_IP):
 			opts1 |= GTSENDV4;
 			break;
@@ -1478,7 +1466,7 @@ static int r8152_tx_csum(struct r8152 *tp, struct tx_desc *desc,
 			goto unavailable;
 		}
 
-		switch (get_protocol(skb)) {
+		switch (vlan_get_protocol(skb)) {
 		case htons(ETH_P_IP):
 			opts2 |= IPV4_CS;
 			ip_protocol = ip_hdr(skb)->protocol;