1. monitor's default port is defined by CEPH_MON_PORT
2. CEPH_PORT_START and CEPH_PORT_LAST are not needed.
Signed-off-by: Changcheng Liu <changcheng.liu@aliyun.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>