vxlan: defer vxlan init as late as possible

When vxlan is compiled as builtin, its init code
runs before IPv6 init, this could cause problems
if we create IPv6 socket in the latter patch.

Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: NCong Wang <amwang@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/vxlan.c

@@ -1771,7 +1771,7 @@ static int __init vxlan_init_module(void)
 out1:
 	return rc;
 }
-module_init(vxlan_init_module);
+late_initcall(vxlan_init_module);
 
 static void __exit vxlan_cleanup_module(void)
 {