net: use IS_ENABLED(CONFIG_IPV6)

Instead of testing defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index 82e803b..eb6b0b7 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -1340,7 +1340,7 @@
 	case AF_INET:
 		dst_ops = &net->xfrm.xfrm4_dst_ops;
 		break;
-#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
+#if IS_ENABLED(CONFIG_IPV6)
 	case AF_INET6:
 		dst_ops = &net->xfrm.xfrm6_dst_ops;
 		break;
@@ -2435,7 +2435,7 @@
 		case AF_INET:
 			xfrm_dst_ops = &net->xfrm.xfrm4_dst_ops;
 			break;
-#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
+#if IS_ENABLED(CONFIG_IPV6)
 		case AF_INET6:
 			xfrm_dst_ops = &net->xfrm.xfrm6_dst_ops;
 			break;
@@ -2485,7 +2485,7 @@
 	afinfo = xfrm_policy_afinfo[AF_INET];
 	if (afinfo)
 		net->xfrm.xfrm4_dst_ops = *afinfo->dst_ops;
-#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
+#if IS_ENABLED(CONFIG_IPV6)
 	afinfo = xfrm_policy_afinfo[AF_INET6];
 	if (afinfo)
 		net->xfrm.xfrm6_dst_ops = *afinfo->dst_ops;