ipv4: fix route mark sparse warning

Sparse complains about RTA_MARK which is should be host order according
to include file and usage in iproute.

net/ipv4/route.c:2223:46: warning: incorrect type in argument 3 (different base types)
net/ipv4/route.c:2223:46:    expected restricted __be32 [usertype] value
net/ipv4/route.c:2223:46:    got unsigned int [unsigned] [usertype] flowic_mark
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv4/route.c

@@ -2220,7 +2220,7 @@ static int rt_fill_info(struct net *net,  __be32 dst, __be32 src,
 		goto nla_put_failure;
 
 	if (fl4->flowi4_mark &&
-	    nla_put_be32(skb, RTA_MARK, fl4->flowi4_mark))
+	    nla_put_u32(skb, RTA_MARK, fl4->flowi4_mark))
 		goto nla_put_failure;
 
 	error = rt->dst.error;