ipv4: Kill RTO_CONN.

It's not used by anything in the kernel, and defined in net/route.h so
never exported to userspace.

Therefore we can safely remove it.
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/route.h

@@ -37,10 +37,6 @@
 
 #define RTO_ONLINK	0x01
 
-#define RTO_CONN	0
-/* RTO_CONN is not used (being alias for 0), but preserved not to break
- * some modules referring to it. */
-
 #define RT_CONN_FLAGS(sk)   (RT_TOS(inet_sk(sk)->tos) | sock_flag(sk, SOCK_LOCALROUTE))
 
 struct fib_nh;