BUG: stream_sock: si->release was not called upon shutw()

BUG: stream_sock: si->release was not called upon shutw()

The ->release function of the stream interface is never called upon
a shutw() because it's placed after a return statement. It is possible
that it has impacted inter-process stick-table replication by preventing
a full resync after certain sequences of connection breakage. Since this
bug has been present since the introduction of the ->release() callback,
it cannot have caused regressions, just possibly non-working situations.

This was detected at Exceliance by Emeric Brun during a code review. It
is 1.5-specific.