qio: non-default context for async conn

We have worked on qio_task_run_in_thread() already.  Further, let
all the qio channel APIs use that context.

Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
diff --git a/chardev/char-socket.c b/chardev/char-socket.c
index 22f6597..b0d1138 100644
--- a/chardev/char-socket.c
+++ b/chardev/char-socket.c
@@ -867,7 +867,7 @@
     tcp_chr_set_client_ioc_name(chr, sioc);
     qio_channel_socket_connect_async(sioc, s->addr,
                                      qemu_chr_socket_connected,
-                                     chr, NULL);
+                                     chr, NULL, NULL);
 
     return false;
 }
@@ -951,7 +951,7 @@
         tcp_chr_set_client_ioc_name(chr, sioc);
         qio_channel_socket_connect_async(sioc, s->addr,
                                          qemu_chr_socket_connected,
-                                         chr, NULL);
+                                         chr, NULL, NULL);
     } else {
         if (s->is_listen) {
             char *name;