[IPV4]: Remove unused multipath cached routing defintion in net/flow.h

Signed-off-by: Rami Rosen <ramirose@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/flow.h

@@ -48,7 +48,6 @@ struct flowi {
 
 	__u8	proto;
 	__u8	flags;
-#define FLOWI_FLAG_MULTIPATHOLDROUTE 0x01
 	union {
 		struct {
 			__be16	sport;