net: use Netdev instead of NetClientOptions in client init

This way we no longer need NetClientOptions and can convert Netdev
into a flat union.

Signed-off-by: Kővágó, Zoltán <DirtY.iCE.hu@gmail.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <93ffdfed7054529635e6acb935150d95dc173a12.1441627176.git.DirtY.iCE.hu@gmail.com>

[rework net_client_init1() to pass Netdev by copying from NetdevLegacy,
rather than merging the two types - which means that we still need
NetClientOptions after all.  Rebase to qapi changes. The bulk of the
patch is mechanical, replacing 'opts' by 'netdev->opts', while
net_client_init1() takes care of converting between legacy and modern
types.]

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1468468228-27827-2-git-send-email-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
diff --git a/net/l2tpv3.c b/net/l2tpv3.c
index 5c668f7..df02f5b 100644
--- a/net/l2tpv3.c
+++ b/net/l2tpv3.c
@@ -524,7 +524,7 @@
     .cleanup = net_l2tpv3_cleanup,
 };
 
-int net_init_l2tpv3(const NetClientOptions *opts,
+int net_init_l2tpv3(const Netdev *netdev,
                     const char *name,
                     NetClientState *peer, Error **errp)
 {
@@ -545,8 +545,8 @@
     s->queue_tail = 0;
     s->header_mismatch = false;
 
-    assert(opts->type == NET_CLIENT_OPTIONS_KIND_L2TPV3);
-    l2tpv3 = opts->u.l2tpv3.data;
+    assert(netdev->opts->type == NET_CLIENT_OPTIONS_KIND_L2TPV3);
+    l2tpv3 = netdev->opts->u.l2tpv3.data;
 
     if (l2tpv3->has_ipv6 && l2tpv3->ipv6) {
         s->ipv6 = l2tpv3->ipv6;