fix commit "mifsetup.c, MIFunsetup(), #1/3 delete broken code"

which silently dropped the
  here->initialized = MIF_FALSE
aspect of the MIFunsetup() function

which caused segfault in testcase
  examples/memristor/memristor_x.sp

src/xspice/mif/mifsetup.c

@@ -515,6 +515,7 @@ MIFunsetup(GENmodel *inModel,CKTcircuit *ckt)
 
                 } /* end for number of ports */
             } /* end for number of connections */
+            here->initialized = MIF_FALSE;
         } /* end for all instances */
 	}
     /* printf("MIFunsetup completed.\n");*/