controller: Wait for switch to disconnect connection
controller: Wait for switch to disconnect connection

If a sender closes a socket immediately after sending some data, a
receiver can fail to receive full data from the sender.

This patch fixes to shutdown a socket with "SHUT_WR" (disallows further
sends only) and enables "Datapath" to wait for a switch to disconnect
the connection.

Signed-off-by: IWASE Yusuke <bb80e84cc9f5a8f01385872ee89032beb5d4eba7@gmail.com>
Signed-off-by: FUJITA Tomonori <93dac1fe9c4b2a3957982200319981492ad4976e@lab.ntt.co.jp>

iwaseyusuke/ryu,lagopus/ryu-lagopus-ext,fujita/ryu,fujita/ryu,lagopus/ryu-lagopus-ext,lagopus/ryu-lagopus-ext,fujita/ryu,lagopus/ryu-lagopus-ext,iwaseyusuke/ryu,osrg/ryu,fujita/ryu,lagopus/ryu-lagopus-ext,fujita/ryu,iwaseyusuke/ryu,iwaseyusuke/ryu,osrg/ryu,osrg/ryu,osrg/ryu,osrg/ryu,iwaseyusuke/ryu