We have a TCP_LOG_CONNEND log that should come out at the very last log of every connection. This
holds some nice stats about why/how the connection ended. Though with the current code it does not
come out without accounting due to the placement of the ifdefs. Also we need to make sure the stacks
fini has ran before calling in from tcp_subr so we get all logs the stack may make at its ending.

Reviewed by: rscheff
Sponsored by: Netflix Inc
Differential Revision:https://reviews.freebsd.org/D39693