firewire: net: remove unused variable 'guid'

GCC reports the following warning with W=1:

drivers/firewire/net.c:493:9: warning:
 variable ‘guid’ set but not used [-Wunused-but-set-variable]
  493 |  __be64 guid;
      |         ^~~~

This variable is not used anymore since commit 6752c8db ("firewire
net, ipv4 arp: Extend hardware address and remove driver-level packet
inspection."). Remove it to fix the warning.
Signed-off-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

drivers/firewire/net.c

@@ -488,9 +488,7 @@ static int fwnet_finish_incoming_packet(struct net_device *net,
 					struct sk_buff *skb, u16 source_node_id,
 					bool is_broadcast, u16 ether_type)
 {
-	struct fwnet_device *dev;
 	int status;
-	__be64 guid;
 
 	switch (ether_type) {
 	case ETH_P_ARP:
@@ -503,7 +501,6 @@ static int fwnet_finish_incoming_packet(struct net_device *net,
 		goto err;
 	}
 
-	dev = netdev_priv(net);
 	/* Write metadata, and then pass to the receive level */
 	skb->dev = net;
 	skb->ip_summed = CHECKSUM_NONE;
@@ -512,7 +509,6 @@ static int fwnet_finish_incoming_packet(struct net_device *net,
 	 * Parse the encapsulation header. This actually does the job of
 	 * converting to an ethernet-like pseudo frame header.
 	 */
-	guid = cpu_to_be64(dev->card->guid);
 	if (dev_hard_header(skb, net, ether_type,
 			   is_broadcast ? net->broadcast : net->dev_addr,
 			   NULL, skb->len) >= 0) {