Change this code so that we don't do a lookup_name() on root.

Change this code so that we don't do a lookup_name() on root.

This matches the lookup failure case in 2.2, and seems to make more sense than
giving the printer to 'world'.  (Avoiding this lookup makes some of my other
changes - including winbind default domains - a little easier).

In any case, tpot has promised to look at this and test it when he gets back to
work. :-)

Andrew Bartlett