Removed generic function (SETF GF-NAME).

An initial reading of the AMOP specification for
ENSURE-GENERIC-FUNCTION made me believe that the name had to be set
AFTER the call to initialize instance.  Reading it again, and having
looked at several examples, I am now convinced that the name of the
generic function should modified by passing the :NAME initarg to
INITIALIZE-INSTANCE or REINITIALIZE-INSTANCE.