ipv6: use ipv6_addr_scope() helper

ipv6_addr_type(&addr)&IPV6_ADDR_SCOPE_MASK could be replaced
by ipv6_addr_scope(), which is slightly faster.

Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv6/addrconf.c

@@ -1126,8 +1126,7 @@ retry:
 
 	ift = !max_addresses ||
 	      ipv6_count_addresses(idev) < max_addresses ?
-		ipv6_add_addr(idev, &addr, tmp_plen,
-			      ipv6_addr_type(&addr)&IPV6_ADDR_SCOPE_MASK,
+		ipv6_add_addr(idev, &addr, tmp_plen, ipv6_addr_scope(&addr),
 			      addr_flags) : NULL;
 	if (IS_ERR_OR_NULL(ift)) {
 		in6_ifa_put(ifp);