tcp: add tracing of skbaddr in tcp_event_skb class

Use the existing parameter and print the address of skbaddr
as other trace functions do.
Signed-off-by: Jason Xing <kernelxing@tencent.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

include/trace/events/tcp.h

@@ -362,7 +362,8 @@ DECLARE_EVENT_CLASS(tcp_event_skb,
 		TP_STORE_ADDR_PORTS_SKB(__entry, skb);
 	),
 
-	TP_printk("src=%pISpc dest=%pISpc", __entry->saddr, __entry->daddr)
+	TP_printk("skbaddr=%p src=%pISpc dest=%pISpc",
+		  __entry->skbaddr, __entry->saddr, __entry->daddr)
 );
 
 DEFINE_EVENT(tcp_event_skb, tcp_bad_csum,