topology/switches: Fix delete port can't immediately remove link.
topology/switches: Fix delete port can't immediately remove link.

If remove port data from self.port_state first,
self.get_port method can't get the port data,
this problem will cause link can't immediately be removed.
This patch remove port data after get_port and link delete.

Signed-off-by: Yu Ren <91b13ed1fbe2b079ee016d7d6e2da33b4a774da1@gmail.com>
Signed-off-by: mgrex97 <91b13ed1fbe2b079ee016d7d6e2da33b4a774da1@gmail.com>
Signed-off-by: FUJITA Tomonori <93dac1fe9c4b2a3957982200319981492ad4976e@lab.ntt.co.jp>

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