Revert commit fe4abe62c7.
The goal was to make sure for health-checks, we would not get sockets in
TIME_WAIT. To do so, we would not call shutdown() if linger_risk is set.
However that is wrong, and that means shutw would never be forwarded to
the server, and thus we could get connection that are never properly closed.
Instead, to fix the original problem as described here :
https://www.mail-archive.com/haproxy@formilux.org/msg34080.html
Just make sure the checks code call cs_shutr() before calling cs_shutw().
If shutr has been called, conn_sock_shutw() will make no attempt to call
shutdown(), as it knows close() will be called.
We should really review and revamp the shutr/shutw code, as described in
github issue #142.
This should be backported to 1.9 and 2.0.
6c7e96a3e1