netfilter: xt_qtaguid: extend iface stat to report protocols

In the past the iface_stat_fmt would only show global bytes/packets
for the skb-based numbers.
For stall detection in userspace, distinguishing tcp vs other protocols
makes it easier.
Now we report
  ifname total_skb_rx_bytes total_skb_rx_packets total_skb_tx_bytes
  total_skb_tx_packets {rx,tx}_{tcp,udp,ohter}_{bytes,packets}

Bug: 6818637
Signed-off-by: JP Abgrall <jpa@google.com>
Change-Id: I179c5ebf2fe822acec0bce4973b4bbb5e7d5076d
net: fix memory leak

i don't know where the memory leak is, but rox says there is. so, don't return if &skb->users isn't 1.

Change-Id: If8c5b4c2f9f0daea73c027839da54283e21169c2
Signed-off-by: Zhao Wei Liew <zhaoweiliew@gmail.com>