Include qapi/qmp/qerror.h exactly where needed

In particular, don't include it into headers.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
diff --git a/migration/savevm.c b/migration/savevm.c
index 2b4e02f..9e0e286 100644
--- a/migration/savevm.c
+++ b/migration/savevm.c
@@ -37,6 +37,7 @@
 #include "qemu/timer.h"
 #include "audio/audio.h"
 #include "migration/migration.h"
+#include "qapi/qmp/qerror.h"
 #include "qemu/error-report.h"
 #include "qemu/sockets.h"
 #include "qemu/queue.h"