Restore missing Event Log entries from SSH layers.

In commit ad0c502ce I forgot to arrange for ssh_connect_ppl to fill in
ppl->logctx, and without it, logevent() was cheerfully throwing away
all those log messages.

ssh.c

@@ -142,6 +142,7 @@ static void ssh_connect_ppl(Ssh *ssh, PacketProtocolLayer *ppl)
     ppl->user_input = &ssh->user_input;
     ppl->seat = ssh->seat;
     ppl->ssh = ssh;
+    ppl->logctx = ssh->logctx;
     ppl->remote_bugs = ssh->remote_bugs;
 }