We test Xyce's capability to detect mutual inductors which have inductors in 
their definitions that are, themselves, defined nowhere else in the netlist 
file.  If Xyce is detecting this scenario properly, running Xyce on bug75.cir 
should produce the error message:

User Fatal: Undefined inductor L2 in mutual inductor K3 definition.

If this message is produced, the test passes.  Otherwise, it fails.
