Update some stale comments regarding tcbinfo locking in the TCP input path: read locks on tcbinfo are no longer used, so won't happen.  No functional change.
Update some stale comments regarding tcbinfo locking in the TCP input
path: read locks on tcbinfo are no longer used, so won't happen.  No
functional change.

MFC after:	3 days

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase