net: fix some sparse errors

make C=2 CF="-D__CHECK_ENDIAN__" M=net

And fix flowi4_init_output() prototype for sport

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/inetpeer.c b/net/ipv4/inetpeer.c
index 86f13c67..986a02b 100644
--- a/net/ipv4/inetpeer.c
+++ b/net/ipv4/inetpeer.c
@@ -136,7 +136,7 @@
 	for (i = 0; i < n; i++) {
 		if (a->addr.a6[i] == b->addr.a6[i])
 			continue;
-		if (a->addr.a6[i] < b->addr.a6[i])
+		if ((__force u32)a->addr.a6[i] < (__force u32)b->addr.a6[i])
 			return -1;
 		return 1;
 	}