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/slirp.c b/net/slirp.c
index 28207b6..ca34bad 100644
--- a/net/slirp.c
+++ b/net/slirp.c
@@ -828,7 +828,7 @@
     return ret;
 }
 
-int net_init_slirp(const NetClientOptions *opts, const char *name,
+int net_init_slirp(const Netdev *netdev, const char *name,
                    NetClientState *peer, Error **errp)
 {
     /* FIXME error_setg(errp, ...) on failure */
@@ -839,8 +839,8 @@
     const char **dnssearch;
     bool ipv4 = true, ipv6 = true;
 
-    assert(opts->type == NET_CLIENT_OPTIONS_KIND_USER);
-    user = opts->u.user.data;
+    assert(netdev->opts->type == NET_CLIENT_OPTIONS_KIND_USER);
+    user = netdev->opts->u.user.data;
 
     if ((user->has_ipv6 && user->ipv6 && !user->has_ipv4) ||
         (user->has_ipv4 && !user->ipv4)) {