migration: Introduce multifd_recv_new_channel()

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
diff --git a/migration/migration.c b/migration/migration.c
index 35f2781..4a7959c 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -449,8 +449,9 @@
     if (!mis->from_src_file) {
         QEMUFile *f = qemu_fopen_channel_input(ioc);
         migration_fd_process_incoming(f);
+        return;
     }
-    /* We still only have a single channel.  Nothing to do here yet */
+    multifd_recv_new_channel(ioc);
 }
 
 /**