Fix test_init_disconnected.
Fix test_init_disconnected.

It failed when the replica set config contains hostnames that differ from the
DB_IP environment variable that PyMongo's tests use. E.g. if DB_IP is
"127.0.0.1" but the replica set is configured to use hostnames like
"localhost:27017", then test_init_disconnected failed because the tests' global
"host" variable is "127.0.0.1" but MongoClient.host is "localhost".

jameslittle/mongo-python-driver,develf/mongo-python-driver,macdiesel/mongo-python-driver,WingGao/mongo-python-driver,mongodb/mongo-python-driver,inspectlabs/mongo-python-driver,macdiesel/mongo-python-driver,mongodb/mongo-python-driver,ramnes/mongo-python-driver,WingGao/mongo-python-driver,gormanb/mongo-python-driver,aherlihy/mongo-python-driver,rychipman/mongo-python-driver,jameslittle/mongo-python-driver,brianwrf/mongo-python-driver,rychipman/mongo-python-driver,ShaneHarvey/mongo-python-driver,bq-xiao/mongo-python-driver,felixonmars/mongo-python-driver,ramnes/mongo-python-driver,develf/mongo-python-driver,ultrabug/mongo-python-driver,ramnes/mongo-python-driver,ShaneHarvey/mongo-python-driver,bq-xiao/mongo-python-driver,aherlihy/mongo-python-driver,gormanb/mongo-python-driver,aherlihy/mongo-python-driver,brianwrf/mongo-python-driver,pigate/mongo-python-driver,ultrabug/mongo-python-driver,mongodb/mongo-python-driver,ameily/mongo-python-driver,felixonmars/mongo-python-driver,ShaneHarvey/mongo-python-driver,pigate/mongo-python-driver,inspectlabs/mongo-python-driver,llvtt/mongo-python-driver,llvtt/mongo-python-driver,ameily/mongo-python-driver