Take out unused cleanup() function so that we can remove the link

dependency on dev.o.

src/core/main.c

 };
 #endif
 
-
 /**************************************************************************
 CLEANUP - shut down networking and console so that the OS may be called 
 **************************************************************************/
+#if 0
 void cleanup(void)
 {
 	/* Stop receiving packets */
 	disable ( &dev );
 	initialized = 0;
 }
+#endif
 
 /*
  * Local variables: