net: ipv4: Pass fib_rt_info as const to fib_dump_info()

fib_dump_info() does not change 'fri', so pass it as 'const'.
It will later allow us to invoke fib_dump_info() from
fib_alias_hw_flags_set().
Signed-off-by: Amit Cohen <amcohen@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net/ipv4/fib_lookup.h

@@ -39,7 +39,7 @@ int fib_nh_match(struct net *net, struct fib_config *cfg, struct fib_info *fi,
 		 struct netlink_ext_ack *extack);
 bool fib_metrics_match(struct fib_config *cfg, struct fib_info *fi);
 int fib_dump_info(struct sk_buff *skb, u32 pid, u32 seq, int event,
-		  struct fib_rt_info *fri, unsigned int flags);
+		  const struct fib_rt_info *fri, unsigned int flags);
 void rtmsg_fib(int event, __be32 key, struct fib_alias *fa, int dst_len,
 	       u32 tb_id, const struct nl_info *info, unsigned int nlm_flags);
 

net/ipv4/fib_semantics.c

@@ -1733,7 +1733,7 @@ static int fib_add_multipath(struct sk_buff *skb, struct fib_info *fi)
 #endif
 
 int fib_dump_info(struct sk_buff *skb, u32 portid, u32 seq, int event,
-		  struct fib_rt_info *fri, unsigned int flags)
+		  const struct fib_rt_info *fri, unsigned int flags)
 {
 	unsigned int nhs = fib_info_num_path(fri->fi);
 	struct fib_info *fi = fri->fi;