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tcp: add two missing addresses when using trace
When I reviewed other people's patch [1], I noticed that similar things
also happen in tcp_event_skb class and tcp_event_sk_skb class. They
don't print those two addrs of skb/sk which already exist.
In this patch, I just do as other trace functions do, like
trace_net_dev_start_xmit(), to know the exact flow or skb we would like
to know in case some systems doesn't support BPF programs well or we
have to use /sys/kernel/debug/tracing only for some reasons.