Minor bug fix; we have some tables with <tr></tr> rows to add a little more space, but this confuses sorttable, so avoid confusion (and an undefined variable).
Minor bug fix; we have some tables with <tr></tr> rows to add a little
more space, but this confuses sorttable, so avoid confusion (and an
undefined variable).

nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome