sctp: Use ipv6_addr_diff() in sctp_v6_addr_match_len().

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sctp/ipv6.c b/net/sctp/ipv6.c
index 240dceb..216d88f 100644
--- a/net/sctp/ipv6.c
+++ b/net/sctp/ipv6.c
@@ -276,20 +276,7 @@
 static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
 					 union sctp_addr *s2)
 {
-	struct in6_addr *a1 = &s1->v6.sin6_addr;
-	struct in6_addr *a2 = &s2->v6.sin6_addr;
-	int i, j;
-
-	for (i = 0; i < 4 ; i++) {
-		__be32 a1xora2;
-
-		a1xora2 = a1->s6_addr32[i] ^ a2->s6_addr32[i];
-
-		if ((j = fls(ntohl(a1xora2))))
-			return (i * 32 + 32 - j);
-	}
-
-	return (i*32);
+	return ipv6_addr_diff(&s1->v6.sin6_addr, &s2->v6.sin6_addr);
 }
 
 /* Fills in the source address(saddr) based on the destination address(daddr)