- netboot: fixed conflicting use of global variables.
  + The function updateNeeded set among others the variable sum2
    which is used later in another context in suse-linuxrc. At
    that point it was expected that the variable is empty for
    the first round in a loop but that's not true if updateNeeded
    called before the loop sets the variable to some content. Thus
    updateNeeded should handle variables used locally in the
    function as real local variables