migration: Clear fd also in error cases

Not clearing the fd and closing the file makes qemu spin using 100%CPU
after incoming migration error.

See for instance bug:
https://bugzilla.redhat.com/show_bug.cgi?id=518032

Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
diff --git a/migration-unix.c b/migration-unix.c
index b7aab38..ce59a2a 100644
--- a/migration-unix.c
+++ b/migration-unix.c
@@ -176,13 +176,12 @@
     qemu_announce_self();
     DPRINTF("successfully loaded vm state\n");
 
-    /* we've successfully migrated, close the server socket */
-    qemu_set_fd_handler2(s, NULL, NULL, NULL, NULL);
-    close(s);
 
 out_fopen:
     qemu_fclose(f);
 out:
+    qemu_set_fd_handler2(s, NULL, NULL, NULL, NULL);
+    close(s);
     close(c);
 }