macvlan: switch to use IS_ENABLED()

Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/if_macvlan.h

@@ -8,7 +8,7 @@
 #include <net/netlink.h>
 #include <linux/u64_stats_sync.h>
 
-#if defined(CONFIG_MACVTAP) || defined(CONFIG_MACVTAP_MODULE)
+#if IS_ENABLED(CONFIG_MACVTAP)
 struct socket *macvtap_get_socket(struct file *);
 #else
 #include <linux/err.h>