Garbage collect never used global, sysctl, externs.

MFC after:	1 week

sys/net/route.c

@@ -116,12 +116,6 @@ VNET_DEFINE(int, rttrash);		/* routes not in table but not freed */
 static VNET_DEFINE(uma_zone_t, rtzone);		/* Routing table UMA zone. */
 #define	V_rtzone	VNET(rtzone)
 
-#if 0
-/* default fib for tunnels to use */
-u_int tunnel_fib = 0;
-SYSCTL_INT(_net, OID_AUTO, tunnelfib, CTLFLAG_RD, &tunnel_fib, 0, "");
-#endif
-
 /*
  * handler for net.my_fibnum
  */

sys/net/route.h

@@ -108,8 +108,6 @@ struct rt_metrics {
 #endif
 
 extern u_int rt_numfibs;	/* number fo usable routing tables */
-extern u_int tunnel_fib;	/* tunnels use these */
-extern u_int fwd_fib;		/* packets being forwarded use these routes */
 /*
  * XXX kernel function pointer `rt_output' is visible to applications.
  */