Rack and BBR broken with the new timewait state purge.

[rrs]

Summary

We recently got rid of the explicit INP_TIMEWAIT state, this has caused some
minor breakage to both rack and bbr. Basically the timewait check that was
in tcp_lro.c is now gone. This means that compressed_ack and mbuf_queued
packets will arrive at TCP without going through tcp_input_with_port(). We need
to expand the check that was stripped to look at the tcp_state (t_state) and
not "LRO" packets that are in the TCPS_TIMEWAIT state.

Test Plan

Make sure with the fix that packets for a connection in time-wait
LRO does not launch the packets via the compressed ack/mbuf queue path.

[glebius]

This is how it gets through! I should also restore the KASSERT()s in rack/bbr, then.