kernel: allow hardware NAT offload drivers to keep a priv pointer

Signed-off-by: Felix Fietkau <nbd@nbd.name>

target/linux/generic/pending-4.14/646-netfilter-nf_flow_table-rework-private-driver-data.patch

@@ -0,0 +1,25 @@
+From: Felix Fietkau <nbd@nbd.name>
+Date: Fri, 27 Apr 2018 14:42:14 +0200
+Subject: [PATCH] netfilter: nf_flow_table: rework private driver data
+
+Move the timeout out of the union, since it can be shared between the
+driver and the stack. Add a private pointer that the driver can use to
+point to its own data structures
+
+Signed-off-by: Felix Fietkau <nbd@nbd.name>
+---
+
+--- a/include/net/netfilter/nf_flow_table.h
++++ b/include/net/netfilter/nf_flow_table.h
+@@ -81,9 +81,10 @@ struct flow_offload_tuple_rhash {
+ struct flow_offload {
+ 	struct flow_offload_tuple_rhash		tuplehash[FLOW_OFFLOAD_DIR_MAX];
+ 	u32					flags;
++	u32					timeout;
+ 	union {
+ 		/* Your private driver data here. */
+-		u32		timeout;
++		void *priv;
+ 	};
+ };
+