[NET]: Unexport {alloc,free}_divert_blk()

these are called by dev.c for every device (and nowhere else)
Signed-off-by: David S. Miller <davem@davemloft.net>

net/core/dv.c

@@ -553,6 +553,3 @@ void divert_frame(struct sk_buff *skb)
 		break;
 	}
 }
-
-EXPORT_SYMBOL(alloc_divert_blk);
-EXPORT_SYMBOL(free_divert_blk);