Fix bug which was displaying "/2 xxx's ... failed ..." when there where no failed nodes for that pc type, it will now display "2 xxx's ... successfully ...".
Fix bug which was displaying "/2 xxx's ... failed ..." when there
where no failed nodes for that pc type, it will now display "2 xxx's
... successfully ...".

Add "no warnings 'uninitialized'" inside loop since I want undefined
to mean zero.  Revert previous (incomplete) fix by checking if it
is defined first.

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